Often, I am asked about the different style of the book of Devarim, Deuteronomy, from the other five books of the Torah. All the other books are written in third person, “And G-d spoke to Moses saying,” etc., while the fifth book is in the first person, where Moses speaks to the Jews directly.
Why is it that this book is written differently than the rest? Especially when this style can confuse people into thinking that Moses is writing it on his own! Well, maybe Moses is. After all, doesn’t the Talmud itself say, “Moses wrote it on his own?” This can be very confusing. If the fifth book is so different, then shouldn’t it be part of the Prophets and not part of the Torah, which is considered to be have been written “by G-d?” How do we reconcile these two ideas, that it is the word of G-d yet it is Moses’s?
There are two ways a student learns and then teaches others. As they first learn and consume the information they are just a conduit, taking it all in, and passing it on to the next person. Of course they have an understanding, but they have not internalized that information; it did not become one with them. They didn’t take ownership of it. Over time, however, they can come to a deeper appreciation of the material they have learned. They start to take ownership of it. They have internalized the information. At this point, they are not sharing it in “third person” any longer; it is theirs. Of course, they will always recognize their teacher and will always give credit to that individual; nevertheless, it becomes theirs.
I am sure you can relate when you catch yourself thinking, “Oh my! I sound like my mother!” The words that you said are your own. However, the message that your mother taught you was incorporated into your being to such an extent that you started thinking and talking exactly like her.
This is the meaning of “G-d spoke through Moses’s mouth.” Moses became so devoted to G-d that when he spoke in first person, it was not because he spoke on his own as in a selfish way, but because he became so selfless that his whole being was about teaching what G-d had taught him.
That is why the fifth book of the Torah is exactly that: a fifth book, part and parcel of G-d’s five books of the Torah.