Rambam-Difference Between Maaseh Merkava and Maaseh Breishis-Yisodei Hatorah perek 4 halacha 10

The Rambam here introduces us into the next subject that he will be talking about. First, he just wants to point out the differences between the two subjects of "Maaseh Merkava" and "Maaseh Bereishis." He says,

כל הדברים האלו שדברנו בענין זה כמר מדלי הם ודברים עמוקים הם. אבל אינם כענין עומק פרק ראשון ושני. וביאור כל אלו הדברים שבפרק שלישי ורביעי הוא הנקרא מעשה בראשית. וכך צוו החכמים הראשונים שאין דורשין בדברים האלו ברבים אלא לאדם אחד מודיעין דברים אלו ומלמדין אותו: 


"All of these things that we have spoken about on this subject are like a drop of water in a bucket and they are very deep. However, they are not as deep as the first two perakim. The subjects that are in the third and fourth perek are known as 'Maaseh breishis' (Acts of Creation). So too the original wise ones commanded us not to explain these subjects in public, rather they should be made known to a single person and taught to him."

The difference that Rambam points out between Maaseh Breishis and Maaseh Merkava is that Maaseh Breishis deals with things that are in the physical world. It talks about the elements of the world, decomposition and physical creation. Basically, Maaseh Breishis can be defined, according to the Rambam, as physics. However, Maaseh Merkava is that which relates to G-D. This deals with G-D's negative attributes and how man connects to Him. Also, the knowledge of the different angels and how they relate to the world are both Maaseh Merkava subjects. This is why the Rambam tells us that the subjects of the first two perakim are deeper and more complex subjects, because metaphysics is harder to understand than physics. Physics deal with the natural world, so man can eventually understand it on his own level. However, metaphysics deals with the connection between man and G-D. The Rambam himself points out that even Moshe never fully comprehended G-D or His characteristics. It is only through understanding what G-D is not, according to the Rambam, that we can have some type of semblance of what G-D is.