Here is Moses, who was learned in all the wisdom of the Egyptians, was not sent by God when he was self-confident, depending on his human power. But God called him only when he said, "Who am I, that I should go to Pharaoh and that I should bring the children of Israel out of Egypt?... I am not eloquent, neither before, nor since you have spoken to Your servant; but I am slow of speech, and slow of tongue." (Ex. 3:11,4:10)