How does Moses convince Pharaoh to release the Israelites?
It was actually God who forced Pharaoh to let the people of Israel go. Through ten plagues he challenged the Egyptian deities, their false gods, and brought his people out of the house of slavery. Moses was only the hand of God for deliverance.
In fact, the Israelites wouldn’t even listen to Moses until he and his brother Aaron showed signs that God told him to show them (Exodus 4:29-31). Moses himself didn’t even want to face Pharaoh. Four times he asks the Lord to choose someone else (Exodus 3:10-4:13).
God’s power in these plagues showed the Egyptian gods and Pharaoh that God is the true God. Each one of the plagues affected one of the Egyptian deities. It was an immediate challenge to their false gods and idols, their magicians who tried to copy some of the plagues, and Pharaoh whose stubborn heart hardened against the Lord.
It took the death of his firstborn son for him to finally stop playing around with the Israelites and letting them go. Even then, he chased them into the Red Sea and lost his own life and army. He was never truly convinced that the Israelites should be let go.
He was so hardened to Moses’ message from God and all of the signs and plagues that it cost him everything. The whole drama began with Israel only asking for a few days in the wilderness to worship the Lord. He refused to grant even that, and it turned into God freeing Israel completely.