Deuteronomy 31:2

I am a hundred and twenty years old - The life of Moses, the great prophet of God and lawgiver of the Jews, was exactly the same in length as the time Noah employed in preaching righteousness to the antediluvian world. These one hundred and twenty years were divided into three remarkable periods: forty years he lived in Egypt, in Pharaoh's court, acquiring all the learning and wisdom of the Egyptians; (see Acts 7:20, Acts 7:23); forty years he sojourned in the land of Midian in a state of preparation for his great and important mission; (Acts 7:29, Acts 7:30); and forty years he guided, led, and governed the Israelites under the express direction and authority of God: in all, one hundred and twenty years.

I am an hundred and twenty years old - The 40 years of the wandering had passed since Moses, then 80 years old, "spake unto Pharaoh" (Exodus 7:7; Compare Deuteronomy 34:7).

I can, no more go out and come in - Render I shall not longer be able to go out and come in: i. e., discharge my duties among you. There is no inconsistency with Deuteronomy 34:7. Moses here adverts to his own age as likely to render him in future unequal to the active discharge of his office as leader of the people: the writer of Deuteronomy 34:1-12, one of Moses' contemporaries, remarks of him that up to the close of life "his eye was not dim, nor his natural force abated" Deuteronomy 31:7; i. e. that he was to the last, in the judgment of others, in full possession of faculties and strength.

31:2 Go out and come in - Perform the office of a leader or governor, because the time of my death approaches.