Wednesday, December 10, 2014

Why Does the Story of Yehuda and Tamar Interrupt the Narrative on Yosef

(Translations from Chabad.org)
In this week's parsha we have the sale of Yosef, the incident of Yehuda with Tamar and then the situation of Yosef with Potifar's wife. A question to ask is why does the story of Yosef's sale get interrupted by Yehuda's shameful story (that seems to have nothing to do with the overall narrative) and then immediately following Yehuda's story we continue the narrative of Yosef by the incident with potifar's wife? Do all three stories really have a lot more to do with one another than it looks like or are they unrelated?

First, we must understand the relationship between Yehuda and Yosef. Yehuda led the brothers to sell Yosef into slavery because, at this point, HE was the leader of the brothers. This can clearly be seen (Genesis 37:26-27),
26And Judah said to his brothers, "What is the gain if we slay our brother and cover up his blood?
כו. וַיֹּאמֶר יְהוּדָה אֶל אֶחָיו מַה בֶּצַע כִּי נַהֲרֹג אֶת אָחִינוּ וְכִסִּינוּ אֶת דָּמוֹ:

27Come, let us sell him to the Ishmaelites, but our hand shall not be upon him, for he is our brother, our flesh." And his brothers hearkened.

כז. לְכוּ וְנִמְכְּרֶנּוּ לַיִּשְׁמְעֵאלִים וְיָדֵנוּ אַל תְּהִי בוֹ כִּי אָחִינוּ בְשָׂרֵנוּ הוּא וַיִּשְׁמְעוּ אֶחָיו:
Therefore, in essence, he was responsible for whatever happened to Yosef. In light of this, we can say that Yehuda was blamed for Yosef's sale (or death) by his father and his brothers. Yehuda came up with the sale AND the lie, as it says (Genesis 37:32),
32And they sent the fine woolen coat, and they brought [it] to their father, and they said, "We have found this; now recognize whether it is your son's coat or not."לב. וַיְשַׁלְּחוּ אֶת כְּתֹנֶת הַפַּסִּים וַיָּבִיאוּ אֶל אֲבִיהֶם וַיֹּאמְרוּ זֹאת מָצָאנוּ הַכֶּר נָא הַכְּתֹנֶת בִּנְךָ הִוא אִם לֹא:
The brothers state, later on by their trip to Egypt, how much they regret what they did to Yosef (Genesis 42:21), 
21And they said to one another, "Indeed, we are guilty for our brother, that we witnessed the distress of his soul when he begged us, and we did not listen. That is why this trouble has come upon us."כא. וַיֹּאמְרוּ אִישׁ אֶל אָחִיו אֲבָל אֲשֵׁמִים | אֲנַחְנוּ עַל אָחִינוּ אֲשֶׁר רָאִינוּ צָרַת נַפְשׁוֹ בְּהִתְחַנְנוֹ אֵלֵינוּ וְלֹא שָׁמָעְנוּ עַל כֵּן בָּאָה אֵלֵינוּ הַצָּרָה הַזֹּאת:
This allows us to understand what happened to Yehuda. After the sale, the Torah tells us (Genesis 28:1),
1Now it came about at that time that Judah was demoted by his brothers, and he turned away until [he came] to an Adullamite man, named Hirah.א. וַיְהִי בָּעֵת הַהִוא וַיֵּרֶד יְהוּדָה מֵאֵת אֶחָיו וַיֵּט עַד אִישׁ עֲדֻלָּמִי וּשְׁמוֹ חִירָה:
The brothers held Yehuda responsible for what they did and they were so distraught that they, essentially, banished him. 


Summing up what happened in the first "ACT" of this week's parsha we can see two main things. First, Yehuda was a leader that used his power to commit a grave sin. Secondly, instead of admitting to the sin, he created this elaborate lie to tell his father and had all of his brothers go along with it. So, the first part of this week's parsha focuses on Yehuda's failure to admit to a sin and this, as far as everyone knew, resulted in Yosef's death. As previously stated, this is why Yehuda was "outside of the camp" after the sale of Yosef.



The next "ACT" in this week's parsha is Yehuda's incident with Tamar, that he slept with her and gave her his signet ring and staff. This story does not, as some people think, come to embarrass Yehuda, but rather to exonerate him. 

In this occurrence we see Yehuda sin and have relations with a prostitute, as far as he knows (Genesis 38:15-16), 
15When Judah saw her, he thought she was a harlot, because she covered her face.
טו. וַיִּרְאֶהָ יְהוּדָה וַיַּחְשְׁבֶהָ לְזוֹנָה כִּי כִסְּתָה פָּנֶיהָ:

16So he turned aside toward her to the road, and he said, "Get ready now, I will come to you," for he did not know that she was his daughter in law, and she said, "What will you give me that you should come to me?"
טז. וַיֵּט אֵלֶיהָ אֶל הַדֶּרֶךְ וַיֹּאמֶר הָבָה נָּא אָבוֹא אֵלַיִךְ כִּי לֹא יָדַע כִּי כַלָּתוֹ הִוא וַתֹּאמֶר מַה תִּתֶּן לִי כִּי תָבוֹא אֵלָי:
However, we see that when Tamar is suspected of sinning in a similar way, becoming pregnant with no husband, Yehuda is ready to condemn her to death (Genesis 38:24),
24Now it came about after nearly three months, that it was told to Judah, saying, "Your daughter in law Tamar has played the harlot, and behold, she is pregnant from harlotry." So Judah said, "Bring her out, and let her be burned."כד. וַיְהִי | כְּמִשְׁלשׁ חֳדָשִׁים וַיֻּגַּד לִיהוּדָה לֵאמֹר זָנְתָה תָּמָר כַּלָּתֶךָ וְגַם הִנֵּה הָרָה לִזְנוּנִים וַיֹּאמֶר יְהוּדָה הוֹצִיאוּהָ וְתִשָּׂרֵף:
It seems a little strange that someone who sinned in a similar manner would be so fast to condemn another in a similar situation. But, this is just human nature. If someone sins in private then they are usually more likely to condemn that sin publicly than someone who is not even involved with that sin.

In any case, when Tamar sends Yehuda his signet ring and staff he immediately confesses to his sin and to Tamar's righteousness, the exact opposite of how he dealt with Yosef's sale (Genesis 38:25-26),
25She was taken out, and she sent to her father in law, saying, "From the man to whom these belong I am pregnant," and she said, "Please recognize whose signet ring, cloak, and staff are these?"
כה. הִוא מוּצֵאת וְהִיא שָׁלְחָה אֶל חָמִיהָ לֵאמֹר לְאִישׁ אֲשֶׁר אֵלֶּה לּוֹ אָנֹכִי הָרָה וַתֹּאמֶר הַכֶּר נָא לְמִי הַחֹתֶמֶת וְהַפְּתִילִים וְהַמַּטֶּה הָאֵלֶּה:

26Then Judah recognized [them], and he said, "She is right, [it is] from me, because I did not give her to my son Shelah." But he no longer continued to be intimate with her.
כו. וַיַּכֵּר יְהוּדָה וַיֹּאמֶר צָדְקָה מִמֶּנִּי כִּי עַל כֵּן לֹא נְתַתִּיהָ לְשֵׁלָה בְנִי וְלֹא יָסַף עוֹד לְדַעְתָּהּ:
In fact, this occurrence proves that Yehuda had done teshuva on his previous actions. By Yosef, Yehuda lied to his father by the sin, but by Tamar, even though it was the most embarrassing thing he could have done, he admitted to his misdeed. Yehuda showed that he had changed his ways and therefore was reaccepted by the brothers and, to this day, the leader of the Jewish people is supposed to come from Yehuda. Thus, the Yehuda type of leader is a leader that makes mistakes, but can admit to them and correct themselves when in error.

Yosef had a very different problem from the one Yehuda had, he was being pursued by his master's wife. However, Yosef never gave in to temptation and was sent to jail because of his integrity. It seems a little backwards here, Yehuda sinned by sleeping with a harlot and admitted to it and was thereby forgiven, but Yosef never gave in to a married woman and was punished for his celibacy? How does that work? 

The way I want to explain this is based on Rashi. Rashi says that Yosef, even in the house of Yaakov, would always make himself look nice and beautiful (Rashi Genesis 37:2),
and he was a lad: He behaved childishly, fixing his hair and touching up his eyes so that he would appear handsome. [From Gen. Rabbah 84:7]והוא נער: שהיה עושה מעשה נערות, מתקן בשערו ממשמש בעיניו, כדי שיהיה נראה יפה:
Basically, Yosef was a little vain, according to Rashi. This might have also been the source as to why Yosef told the brothers his dreams, because he was a little vain.

Later, we see that Yosef was in a household where the master's wife would always try to seduce him. Perhaps Yosef should not have been making himself look nice all the time and thereby Potifar's wife would have stopped pursuing him (Rashi Genesis 39:6),

and Joseph had handsome features: As soon as Joseph found himself [in the position of] ruler, he began eating and drinking and curling his hair. Said the Holy One, blessed be He: “Your father is mourning and you curl your hair! I will incite the bear against you.” Immediately afterwards“his master’s wife lifted up her eyes.” [from Tanchuma Vayeshev 8]ויהי יוסף יפה תואר: כיון שראה עצמו מושל, התחיל אוכל ושותה ומסלסל בשערו, אמר הקב"ה אביך מתאבל ואתה מסלסל בשערך, אני מגרה בך את הדוב מיד:

We see from here that, at this point, Yosef had not changed his ways, he was the same. Being sold into slavery never evoked a character change in Yosef. Yehuda, on the other hand, was able to realize his faults and do teshuva. This could be a possible explanation as to why all of these three stories are together and why Yosef was punished, but Yehuda was exonerated. These three stories teach us the power and importance of Teshuva. Yosef did not become humble and change his ways until after he was imprisoned, but Yehuda was able to change his ways once he realized his own hypocrisy.

This difference is seen in two different leaders later on in Tanach as well, King Saul and King David. King Saul had sinned by the war with Amalek by not listening to G-D and then denying his sin. As it says (Samuel 1 15:14-26),
14And Samuel said, "What then is this bleating of the sheep in my ears? And the lowing of the oxen which I hear?"
יד. וַיֹּאמֶר שְׁמוּאֵל וּמֶה קוֹל הַצֹּאן הַזֶּה בְּאָזְנָי וְקוֹל הַבָּקָר אֲשֶׁר אָנֹכִי שֹׁמֵעַ:

15And Saul said, "They brought them from the Amalekites, for the people had pity on the best of the sheep, and the oxen, in order to sacrifice to the Lord your God: and the rest we have utterly destroyed."
טו. וַיֹּאמֶר שָׁאוּל מֵעֲמָלֵקִי הֱבִיאוּם אֲשֶׁר חָמַל הָעָם עַל מֵיטַב הַצֹּאן וְהַבָּקָר לְמַעַן זְבֹחַ לַיהֹוָה אֱלֹהֶיךָ וְאֶת הַיּוֹתֵר הֶחֱרַמְנוּ:

16And Samuel said to Saul, "Desist, and I shall tell you what the Lord spoke to me last night." And he said to him, "Speak."
טז. וַיֹּאמֶר שְׁמוּאֵל אֶל שָׁאוּל הֶרֶף וְאַגִּידָה לְּךָ אֵת אֲשֶׁר דִּבֶּר יְהֹוָה אֵלַי הַלָּיְלָה וַיֹּאמֶר לוֹ דַּבֵּר:

17And Samuel said, "Even if you are small in your own eyes, are you not the head of the tribes of Israel? And the Lord anointed you as king over Israel.
יז. וַיֹּאמֶר שְׁמוּאֵל הֲלוֹא אִם קָטֹן אַתָּה בְּעֵינֶיךָ רֹאשׁ שִׁבְטֵי יִשְׂרָאֵל אָתָּה וַיִּמְשָׁחֲךָ יְהֹוָה לְמֶלֶךְ עַל יִשְׂרָאֵל:

18And the Lord sent you on a mission, and said, 'Go, and you shall utterly destroy the sinners, the Amalekites, and you shall wage war against them until they destroy them.'
יח. וַיִּשְׁלָחֲךָ יְהֹוָה בְּדָרֶךְ וַיֹּאמֶר לֵךְ וְהַחֲרַמְתָּה אֶת הַחַטָּאִים אֶת עֲמָלֵק וְנִלְחַמְתָּ בוֹ עַד כַּלּוֹתָם אֹתָם:

19Now, why did you not hearken to the voice of the Lord, but you flew upon the spoil, and you did what was evil in the eyes of the Lord?"
יט. וְלָמָּה לֹא שָׁמַעְתָּ בְּקוֹל יְהֹוָה וַתַּעַט אֶל הַשָּׁלָל וַתַּעַשׂ הָרַע בְּעֵינֵי יְהֹוָה:

20And Saul said to Samuel, "Yes, I did hearken to the voice of the Lord. I did go on the mission on which the Lord sent me, and I brought Agag, the king of Amalek alive, and have utterly destroyed the Amalekites.
כ. וַיֹּאמֶר שָׁאוּל אֶל שְׁמוּאֵל אֲשֶׁר שָׁמַעְתִּי בְּקוֹל יְהֹוָה וָאֵלֵךְ בַּדֶּרֶךְ אֲשֶׁר שְׁלָחַנִי יְהֹוָה וָאָבִיא אֶת אֲגַג מֶלֶךְ עֲמָלֵק וְאֶת עֲמָלֵק הֶחֱרַמְתִּי:

21And the people took from the spoil, sheep and oxen, the best of the ban, to sacrifice to your God in Gilgal."
כא. וַיִּקַּח הָעָם מֵהַשָּׁלָל צֹאן וּבָקָר רֵאשִׁית הַחֵרֶם לִזְבֹּחַ לַיהֹוָה אֱלֹהֶיךָ בַּגִּלְגָּל:

22And Samuel said, "Has the Lord (as much) desire in burnt offerings and peace-offerings, as in obeying the voice of the Lord? Behold, to obey is better than a peace-offering; to hearken (is better) than the fat of rams.
כב. וַיֹּאמֶר שְׁמוּאֵל הַחֵפֶץ לַיהֹוָה בְּעֹלוֹת וּזְבָחִים כִּשְׁמֹעַ בְּקוֹל יְהֹוָה הִנֵּה שְׁמֹעַ מִזֶּבַח טוֹב לְהַקְשִׁיב מֵחֵלֶב אֵילִים:

23For rebellion is as the sin of divination, and stubbornness is as idolatry and teraphim. Since you rejected the word of the Lord, He has rejected you from being a king."
כג. כִּי חַטַּאת קֶסֶם מֶרִי וְאָוֶן וּתְרָפִים הַפְצַר יַעַן מָאַסְתָּ אֶת דְּבַר יְהֹוָה וַיִּמְאָסְךָ מִמֶּלֶךְ:

24And Saul said to Samuel, "I have sinned, for I transgressed the Lord's command, and your words, for I feared the people, and I hearkened to their voice.
כד. וַיֹּאמֶר שָׁאוּל אֶל שְׁמוּאֵל חָטָאתִי כִּי עָבַרְתִּי אֶת פִּי יְהֹוָה וְאֶת דְּבָרֶיךָ כִּי יָרֵאתִי אֶת הָעָם וָאֶשְׁמַע בְּקוֹלָם:

25And now, forgive now my sin, and return with me, and I shall prostrate myself to the Lord."
כה. וְעַתָּה שָֹא נָא אֶת חַטָּאתִי וְשׁוּב עִמִּי וְאֶשְׁתַּחֲוֶה לַיהֹוָה:

26And Samuel said to Saul, "I shall not return with you, for you have rejected the word of the Lord, and the Lord has rejected you from being a king over Israel."
כו. וַיֹּאמֶר שְׁמוּאֵל אֶל שָׁאוּל לֹא אָשׁוּב עִמָּךְ כִּי מָאַסְתָּה אֶת דְּבַר יְהֹוָה וַיִּמְאָסְךָ יְהֹוָה מִהְיוֹת מֶלֶךְ עַל יִשְׂרָאֵל:
This is similar to Yosef. Saul was a humble person and because of his inability to control his humbleness he allowed himself to sin. Not only did he sin, but he denied the fact that he was doing the wrong thing. Yosef, too, could not even realize that beautifying himself was the wrong thing to do.

However, the story of Dovid shows someone who sinned, a terrible sin as is explained elsewhere on this blog (http://markset565.blogspot.com/2010/06/what-happened-between-bas-bat-sheva-and.html), was able to immediately repent when his errors are pointed out to him. He did not deny the sin, but immediately accepted the rebuke and changed because of it.

This is the lesson we must take away, Saul and Yosef were great people, but they could not understand where they were lacking. This is why Yosef not only was sold into slavery, but was then thrown into jail, and why Saul lost his kingship. However, Yehuda and Dovid committed even greater sins than Yosef or Saul, but because they were horrified and disappointed with themselves because of their sins they repented and kept or regained their leadership roles. This just shows how great the act of repentance is.

Tuesday, October 7, 2014

Rambam- Yesodei HaTorah- Chapter 9 Halacha 1: No Prophet Can Alter The Torah and G-D's Knowledge of the Future

 דבר ברור ומפורש בתורה שהיא מצוה עומדת לעולם ולעולמי עולמים אין לה לא שינוי ולא גרעון ולא תוספת שנאמר את כל הדבר אשר אנכי מצוה אתכם אותו תשמרון לעשות לא תוסף עליו ולא תגרע ממנו. ונאמר והנגלות לנו ולבנינו עד עולם לעשות את כל דברי התורה הזאת. הא למדת שכל דברי תורה מצווין אנו לעשותן עד עולם. וכן הוא אומר חוקת עולם לדורותיכם. ונאמר לא בשמים היא. הא למדת שאין נביא רשאי לחדש דבר מעתה. לפיכך אם יעמוד איש בין מן האומות בין מישראל ויעשה אות ומופת ויאמר שה' שלחו להוסיף מצוה או לגרוע מצוה או לפרש במצוה מן המצות פירוש שלא שמענו ממשה. או שאמר שאותן המצות שנצטוו בהן ישראל אינן לעולם ולדורי דורות אלא מצות לפי זמן היו. הרי זה נביא שקר שהרי בא להכחיש נבואתו של משה. ומיתתו בחנק על שהזיד לדבר בשם ה' אשר לא צוהו. שהוא ברוך שמו צוה למשה שהמצוה הזאת לנו ולבנינו עד עולם ולא איש אל ויכזב: 

It is a clear [idea] in the Torah that it (the Torah) is a [conglomeration] of commandment[s] that were established to last forever. It is not [meant] to have any changes, deletions, or additions, as it says (Devarim 13:1), "Everything I command you, be careful to do it. You shall neither add to it, nor subtract from it." It also says (Devarim 29:28), " But the revealed things are for us and our children forever: that we must fulfill all the words of this Torah." This is to teach us that all of the words of the Torah are commands for us to perform, forever. It also says (Vayikra 23:14), "An eternal statute throughout your generations." 
It also says (Devarim 30:12), "It is not in heaven." This teaches us that the prophet does not have permission to [reveal a] new [law that was not revealed previously.] Therefore, if a prophet arises from among the men of Israel or from among the nations and performs signs and wonders and then says that G-D sent him to add a commandment, to delete a commandment, to explain one of the existing commandments in a way that was not heard from Moshe, or he says the commandments that Israel were commanded to follow were not meant for the generations, but only for a specific time, this [person] is a false prophet because he is coming to contradict the prophecy of Moshe! His death penalty is strangulation because he [falsely claimed] to be speaking in the name of G-D, but he was not really commanded [by G-D.] For, [G-D] commanded Moshe that this testament (the Torah) was for us and our children for eternity and [G-D] is not like a man, who lies.    

The Rambam here is introducing us to the idea that once the Torah was given to Moshe, that is the final draft of the Torah. G-D was working on the Torah and was "tweaking it" until he finally gave it to Moshe and the Jews at Mount Sinai. However, once G-D gave the Torah, that was it. There was no more alterations, G-D wanted the Torah that was handed over to be the final draft. Any further alterations were unnecessary. Therefore, if a prophet comes and says, "G-D wanted to tweak the Torah a little more," we call him or her a liar. The reason is because the Torah was given and it is "no longer in heaven!" Man was given the perfect code.

How do we know this code was perfect and no future alterations are necessary? For starters, it was given to us by G-D. If G-D is perfect and omniscient then the code he gave us must apply for all time.  

This brings me to an interesting and very important discussion, does G-D know the future and if he does, how can there be free will?

This has been a personal struggle for me and I believe I have a decent explanation. However, first let me state the dilemma clearly. The problem is this: If G-D knows what a person will do, then how does that person have free will to perform that action? Is the person not forced into performing that action because G-D already knows it will occur?

There are three main sources to discuss if you are interested in the rationalist approach to G-D's foreknowledge. The statements made by Rabbi Akiva, the Rambam and the Ralbag. Let's start with Rabbi Akiva. 

It states in the name of Rabbi Akiva in Pirkei Avos (Ethics of our fathers, 3:15), "All is foreseen, and freedom of choice is granted." This does not help us understand anything. It is a simple statement that allows us to say that we have freedom of choice, but G-D knows everything. It seems like a contradiction, but it isn't and we must take Rabbi Akiva's word for it. This is a very unsatisfying answer. 

The Rambam gives us a little more, but not much. He bases his opinion on his approach to divine attributes (found in The Guide section 1 chapters 51-68). Basically, the Rambam says G-D's foreknowledge does not remove our freedom from our choices (See The Guide section 3 chapter 20). The reason for this is because we don't understand the idea of G-D Knowing something. G-D does not have features that are knowable. We do not have the ability to understand any attributes of G-D, therefore, we can not understand why His knowledge of events does not contradict our free will, but it does not. This answer is more detailed than Rabbi Akiva's, but it is still very unsatisfying.


The Ralbag's answer is intriguing, because he has such a unique approach to G-D's foreknowledge. He explains (In section 3 of The Wars of The Lord) that G-D does not know the future, because the future has not yet occurred, but G-D knows all of the possible outcomes based on different decisions that a person can make.


All three of these answers are difficult to take. Rabbi Akiva does not give any explanations as to why or how his statement is believable. The Rambam gives an explanation that would disallow any type of logic in Judaism, because if we can't really understand anything about G-D how can we truly understand what he said or passed down to us? Finally, the Ralbags approach would take away too much power from G-D. For, if G-D does not know the future, how can His Torah be relevant for all generations and unchangeable, like the Rambam says it is (Granted the Ralbag goes on to explain this difficulty, but the answers are still unsatisfying)?


I think the following approach makes the most sense. All of these previous approaches either lacked a way of explaining something or were the best effort for the thinking of their time. However, if we understand that space and time are finite and G-D exists outside of the finite universe, then we can understand that G-D knows everything that has occurred and everything that will occur. It is similar to watching a movie for the second time, just because I know what is going to happen in the movie, does that make the choices of the person in the movie any less of a choice? Also, it must be that G-D knows all future events in order for the Rambam's approach to be valid, because, as I stated earlier, if G-D did not know the future how could the Torah be unalterable? Obviously, the Torah would need to adjust as reality changed. However, with our approach, using a superficial understanding of space and time, we can somewhat understand how G-D's knowledge of the future works. 

Sunday, May 4, 2014

Rambam-Mishna Torah Yisodei Hatora Chapter 8 Mishna 3: Why a Prophet's Miracles Do Not Prove Anything

לפיכך אם עמד הנביא ועשה אותות ומופתים גדולים ובקש להכחיש נבואתו של משה רבינו אין שומעין לו ואנו יודעין בבאור שאותן האותות בלט וכשוף הן. לפי שנבואת משה רבינו אינה על פי האותות כדי שנערוך אותות זה לאותות זה. אלא בעינינו ראינוה ובאזנינו שמענוה כמו ששמע הוא. הא למה הדבר דומה לעדים שהעידו לאדם על דבר שראה בעיניו שאינו כמו שראה שאינו שומע להן אלא יודע בודאי שהן עדי שקר. לפיכך אמרה תורה שאם בא האות והמופת לא תשמע אל דברי הנביא ההוא. שהרי זה בא אליך באות ומופת להכחיש מה שראית בעיניך והואיל ואין אנו מאמינים במופת אלא מפני המצות שצונו משה היאך נקבל מאות זה שבא להכחיש נבואתו של משה שראינו וששמענו:

Therefore, if a prophet arises and performs great wonders and miracles and tries to contradict the prophecy of Moshe, our teacher, we do not listen to him and we know with certainty that those wonders [were performed with] trickery and magic. For, the prophecy of Moshe, our teacher, was not [based] on the signs [he performed] so we could compare this sign to another [prophet's] sign. Rather, we saw with our eyes and heard with our ears like [Moshe] heard. This [prophet that is giving a prophecy that contradicts Moshe's prophecy] is similar to witnesses that testify to a man concerning something that he saw with his own eyes, [but they claim to have] seen something different than what this man saw and different from what this man heard, therefore, this man knows with certainty that these are false witnesses. Therefore, the Torah says that if a false prophet comes with signs and wonders, you should not listen to his words, because this [false prophet] is bringing you signs and wonders to contradict something that you have seen with your own eyes. And since we only believe in wonders because of the commandments that Moshe commanded us, how can we accept this sign that is being brought to contradict the prophecy of Moshe that we saw and we heard?  

The Rambam here bases this Mishna on a foundation of his philosophy. The Rambam believes that there is no such thing as an unnatural event that occurs in this world, except for those things that G-D built into creation to be unnatural. This is found in the Rambam's explanation on the Mishna in Avos (Perek 5) that speaks about the ten things that were created on the eve of Sabbath. Over there, the Rambam says that all miracles and wonders are within the realm of the natural. 

With this in mind, we can understand his stance that a prophet producing a miracle proves nothing, because this miracle is within the realm of nature. However, the Torah, G-D and Moshe's prophecy are supernatural and thus, "untouchable" by any subsequent prophet. Every miracle is a natural phenomenon and thus can not be used to overrule something supernatural that is experienced with the senses. This is why we believe in miracles only because of Moshe's prophecy, because that is what brought the supernatural into this world. Without Moshe speaking to G-D and the Jewish people witnessing it, we would not believe that anything is supernatural.