Genesis 12:11-13

Abram went to Egypt, which was a foreign country. He did not know its customs. He was not confident that God would protect him and Sarai. He thought that someone might kill him in order to take Sarai as a wife. So he decided to say that Sarai was his sister. And, if anyone took Sarai as a wife, he would not kill Abram. And so perhaps Abram and Sarai would escape before the wedding. But the person who took Sarai was *Pharaoh, the king of Egypt. And when Sarai was in *Pharaoh’s court, she could not escape.

When Abram called Sarai his sister, he did not tell the truth. But what he said was not completely wrong. Sarai was Abram’s half-sister. Sarai and Abram had the same father but they did not have the same mother. (See Genesis 20:12.) At that time, some people married their half-sisters. Later, the Bible said that a marriage with a half-sister is wrong. (See Deuteronomy 27:22.)