Who hath made man's mouth! God could and would have cured the defect in Moses' speech, whatever it was; could and would have added eloquence to his other gifts, if he had even at this point yielded himself up unreservedly to his guidance and heartily accepted his mission.
Nothing is too hard for the Lord. He gives all powers—sight, and hearing, and speech included—to whom he will. He would have been "with Moses' mouth," removing all hesitation or indistinctness, and have "taught him what to say"—supplied the thought and the language by which to express it—if Moses would have let him.
But the reply in Exodus 4:13 shut up the Divine bounty, prevented its outpour, and left Moses the ineffective speaker which he was content to be. The words, O my Lord, send, I pray thee, by the hand of him whom Thou wilt send, are curt and ungracious; much curter in the original than in our version.
£ They contain a grudging acquiescence. But for the deprecatory particle with which they commence—the same as in Exodus 4:10, they would be almost rude. And we see the result in the next verse.