There was a grievous famine in the land. Abram went down into Egypt to stay temporarily there.
Abram (to Sarai his wife): You are a fair woman. When the Egyptians see you, they shall say, This is his wife. They will kill me, but they will save you alive. So, say you are my sister, that it may be well with me for your sake; and my soul shall live because of you.
When Abram was come into Egypt, the Egyptians beheld the woman that she was very fair.
The princes of Pharaoh also saw her and commended her before Pharaoh. Sarai was taken into Pharaoh’s house. The Pharaoh entreated Abram well for her sake. He had sheep, and oxen, and he asses, and menservants, and maidservants, and she asses, and camels.
And the Lord plagued Pharaoh and his house with great plagues because of Sarai Abram’s wife.
Pharaoh (to Abram): What is this that you have done to me? Why didn’t you tell me that she was your wife? Why did you say, She is my sister? I might have taken her to me to wife: now therefore take your wife and go your way.
Pharaoh commanded his men concerning Abram. They sent Abram away, and his wife and all that he had.
Some would say that Sarai lied. But she actually was Abram’s sister (his half-sister).
Genesis 20:12 Abram says, Indeed Sarai is my sister; she is the daughter of my father, but not the daughter of my mother; and she became my wife