In the 5th chapter of Tanya the old rebbe brings a saying from Zohar in the name of Elijah the prophet: "you (G-d) are higher than everyone and no thought can grasp you". The rebbe asks a question: the term 'grasp' is said only regarding physical things, but regarding something spiritual one can say 'I understand you' but one cannot say 'I grasped your thought' if so why does the Zohar say the term 'grasp' regarding G-d?                                  The rebbe explains: when a person understands something in Torah fully, the thing that he understands is inside his brain and it also surrounds his brain at the same time. And this part of Torah that the person learned is G-ds wisdom and will, which G-d decided that this particular thing is permitted and this particular thing is forbidden. And G-d ''minimized'' 'so to speak' his will and wisdom into the Torah the 613 commandments. So when a person learns Torah, G-ds wisdom is inside of him and surrounding him from all sides. Which this is something you cannot have physically, because in physicality you cannot surround something while it is surrounding you. But all the above is only regarding G-ds will and wisdom, but no one can understand G-d himself because he is unlimited. And that is why Torah is called 'food for the soul', because just like the food becomes a part of the body and grows with it externally and internally, also the Torah goes into the person and becomes a part of him and it also surrounds him. And this is why it says that after a person passes away and his soul goes up, the 'food' for his soul is the Torah that he learned down here, and the 'cloths' for his soul are the 'mitzvoth' that he did during his life. Because the Torah is externally and internally but when one does a mitzvah, G-ds will surrounds him but it's not inside of him, therefore the 'mitzvoth' are called 'cloths'.