Let me alone. — This was not a command to abstain from deprecation, but rather an intimation that deprecation might have power to change God’s purpose. Moses was tried by an offer which would have exalted him at the expense of the people. He was allowed to see that he might either sacrifice the people and obtain his own aggrandisement, or deny himself and save them. That he chose the better part redounds to his undying glory.
I will make of thee a great nation — i.e., I will put thee in the place of Abraham, make thee the father of the faithful, destroy all existing Israelites but thee and thine, and proceed de novo to raise up a “great nation” out of thy loins.