And he said unto them, I [am] an hundred and twenty years old this day,.... Whether the meaning is, that that day precisely was his birthday, is a question; it may be the sense is only this, that he was now arrived to such an age; though Jarchi takes it in the first sense, to which are objected his words in De 31:14; yet it seems by De 32:48 that having delivered to the children of Israel the song he was ordered this day to write, on the selfsame day he was bid to go up to Mount Nebo and die: and it is a commonly received tradition with the Jews, that Moses died on the same day of the month he was born;See Gill on "De 34:7".
I can no more go out and come in; not that he could no longer go out of his tent and return without great trouble and difficulty, being so decrepit; but that he could not perform his office as their ruler and governor, or go out to battle and return as their general; and this not through any incapacity of body or mind, both being vigorous, sound, and well, as is clear from De 34:7; but because it was the will of God that he should live no longer to exercise such an office, power, and authority:also the Lord hath said unto me, or "for the Lord has said" , and so is a reason of the foregoing; the Targum is,"the Word of the Lord said:''thou shalt not go over this Jordan: to which he and the people of Israel were nigh, and lay between them and the land of Canaan, over which it was necessary to pass in order to go into it; but Moses must not lead them there, this work was reserved for Joshua, a type of Christ; not Moses and his law, or obedience to it, is what introduces any into the heavenly Canaan only Jesus and his righteousness; see De 3:27.
hwhyw "praesertim cum et Dominus", V. L. w sometimes signifies "for". See Noldius, p. 285.