How important is it to be one of God’s covenant people?
Genesis 20 provides some insight.
Frankly, Abraham doesn’t come off very well here. He’s still telling people Sarah is his sister, and still using the excuse that he fears for his life – this despite the fact that he’s already routed a coalition of four oppressive kings with much larger armies. On top of that, he has married his step-sister which will, under the law, be a crime (Leviticus 18:9).
So . . . he’s a liar and a coward. Or perhaps, something else equally repugnant.
And yet, when the consequences of his actions result in King Abimelech taking Sarah for his wife, it is Abimelech who is reprimanded by God. In fact, despite Abimelech’s innocence, God punishes Abimelech’s household with barrenness and threatens Abimelech himself with death.
To add insult to injury, God tells Abimelech to ask Abraham to pray for him because “he is a prophet.”
The whole story is to get you to see not that God excuses Abraham’s behavior, but simply that he has a different, closer, and better relationship with God because he is in covenant with God.
If Abraham’s stature is underscored with this story, I’d say there is something also there about Sarah. She is nearly a hundred years old and Abimelech the king finds her desirable. It’s not that God’s people just behave differently from others. Their difference goes to the core of their being.
One more thought: whatever we think of Abraham’s character at this point, Abimelech certainly made him think Abimelech was a threat. And yet, Abraham was called on to pray for Abimelech’s welfare. Covenant people must love their enemies and pray for them. It’s what Jesus said, but also what God always intended.