John Gill Commentary Exodus 33:12

"And Moses said unto Jehovah, See, thou sayest unto me, Bring up this people: and thou hast not let me know whom thou wilt send with me. Yet thou hast said, I know thee by name, and thou hast also found favor in my sight." — Exodus 33:12 (ASV)

And Moses said unto the Lord
Having returned from the camp to the tabernacle again;

see, you say unto me, bring up this people :
from hence to the land of Canaan, as in (Exodus 33:1)

and you have not let me know whom you will send with me ;
to guide and direct him, help and assist him, protect and defend him, and the people with him; he had signified something of this kind, but by some expressions, and by his present conduct, he was at a loss to know who was to go with him: he had told him that the uncreated Angel, in whom his name and he himself were, should go with them; but now it had been declared that he would not go up in the midst of them himself, but send an angel, a created one, but who that was he knew not; he thought he had reason to expect the pillar of the cloud and fire by day and night; but that had had so many motions that he could not be assured of the continuance of it:

yet you have said, I know you by name ;
have a particular and special knowledge of you, and distinguished you from others, and have a personal affection for you:

and you have also found grace in my sight :
had an interest in his special favour and good will, was acceptable unto him, had received an abundance of spiritual grace, and many very extraordinary gifts from him, and had had many benefits bestowed on him, which were proofs of his being grateful and well pleasing to him.