John Gill Commentary Deuteronomy 1:11

"Jehovah, the God of your fathers, make you a thousand times as many as ye are, and bless you, as he hath promised you!" — Deuteronomy 1:11 (ASV)

The Lord God of your fathers make you a thousand times so many
more as ye are
This prayer he made, or this blessing he pronounced on them, to show that he did not envy their increase, nor was any ways uneasy at it, but rejoiced in it, though he gave it as a reason of his not being able to govern them alone:

and bless you, as he has promised you :
with all kind of blessings, as he had often promised their fathers.