Charles Ellicott Commentary Exodus 32:10

"now therefore let me alone, that my wrath may wax hot against them, and that I may consume them: and I will make of thee a great nation." — Exodus 32:10 (ASV)

Let me alone. —This was not a command to abstain from pleading, but rather an indication that pleading might have power to change God’s purpose. Moses was tried by an offer that 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 aggrandizement, or deny himself and save them. That he chose the better part contributes to his undying glory.

I will make of thee a great nation —that is, I will put you in the place of Abraham, make you the father of the faithful, destroy all existing Israelites except you and yours, and proceed de novo to raise up a “great nation” from your loins.