What does Genesis 20:7 mean?

Now give the man’s wife back to him. He’s a prophet, and he’ll pray for you so you’ll live. But if you don’t return her, you and everyone with you will die. Genesis 20:7 - Modern Text Bible

(God tells Abimelech to return Sarah to Abraham, warning that there will be deadly consequences if he doesn’t. Abraham’s role as a prophet is highlighted.)