What was Moses still saying at Exodus 4:10 after God commissioned him?
Moses was still claiming he could not do it, revealing his timidity after God's commission. He had spent forty years on the backside of the desert herding sheep, with almost no contact with public or populated areas, and had consequently become insecure about confronting Pharaoh and bringing Israel out of bondage.
Les explains that Moses had been commissioned by God to go and confront Pharaoh for the distinct purpose of bringing Israel out of bondage. The first difficulty was overcoming Moses' own timidity. At Exodus 4:10, where the previous program left off, Moses is still claiming he cannot do it. Les gives the reason: Moses had been forty years on the backside of the desert herding sheep. He had almost no contact with the public or with populated areas, and had consequently gotten to the place where he was insecure.
And Moses said unto the LORD, O my LORD, I am not eloquent, neither heretofore, nor since thou hast spoken unto thy servant: but I am slow of speech, and of a slow tongue.