Exodus 6:9-13

9So Moses spoke thus to the children of Israel; but they did not heed Moses, because of anguish of spirit and cruel bondage.

10And the Lord spoke to Moses, saying,

11“Go in, tell Pharaoh king of Egypt to let the children of Israel go out of his land.”

12And Moses spoke before the Lord, saying, “The children of Israel have not heeded me. How then shall Pharaoh heed me, for I am of uncircumcised lips?”

13Then the Lord spoke to Moses and Aaron, and gave them a command for the children of Israel and for Pharaoh king of Egypt, to bring the children of Israel out of the land of Egypt.