Genesis 18:8-10 American Standard Version (ASV)
8 And he took butter, and milk, and the calf which he had dressed, and set it before them; and he stood by them under the tree, and they did eat.
9 And they said unto him, Where is Sarah thy wife? And he said, Behold, in the tent. 10 And he said, I will certainly return unto thee when the season [a]cometh round; and, lo, Sarah thy wife shall have a son. And Sarah heard in the tent door, which was behind him.