After they blew up Sodom and Gomorrah, Abraham packed up and took off for Gerar which nowadays would be the southern part of modern day Palestine. Here he ran into Abimelech who was the king of that particular area.
For some reason Abraham thought the locals would kill him to get to Sarah, so Abraham told Sarah to tell everybody that she was his sister (which she was), and not his wife. Why anyone would want a 90 year old, post-menopausal woman is beyond me but that shows what I know because Abimelech immediately swooped in and scooped her up.
But before he could do anything inappropriate God came to him in a dream and said he was going to kill him for taking another man’s wife. “Whoa now there God!,” says Abimelech, “This guy said she’s my sister. What am I supposed to do?” And God says, “Well, okay, just give her back.” 1
Relieved, Abimelech gave Sarah back to Abraham, along with a bunch of sheep, cattle, slaves and money and said “My land is before you, dwell where it pleases you.” In other words, “Take your wife and hit the road.”
The funny thing is that Abraham and Sarah had done this same thing about 25 years earlier when they went to Egypt.2 Except that time it was Pharaoh who’d snatched up Sarah. I’m guessing she was better looking back then but still, you’d think Pharaoh could do better.
However they did it, they got the same result. God told Pharaoh to give her back, or else, which he did, along with lots of sheep, cattle, and servants. This was the beginning of Abraham’s wealth building.
Were Abraham and Sarah working a con? Sure sounds like it.
1] I paraphrase here
2] Genesis 12:11-20