Genesis 18:1-15 NKJV
Then the LORD appeared to him by the terebinth trees of Mamre, as he was sitting in the tent door in the heat of the day. So he lifted his eyes and looked, and behold, three men were standing by him; and when he saw them, he ran from the tent door to meet them, and bowed himself to the ground, and said, “My Lord, if I have now found favor in Your sight, do not pass on by Your servant. Please let a little water be brought, and wash your feet, and rest yourselves under the tree. And I will bring a morsel of bread, that you may refresh your hearts. After that you may pass by, inasmuch as you have come to your servant.”
They said, “Do as you have said.”
So Abraham hurried into the tent to Sarah and said, “Quickly, make ready three measures of fine meal; knead it and make cakes.” And Abraham ran to the herd, took a tender and good calf, gave it to a young man, and he hastened to prepare it. So he took butter and milk and the calf which he had prepared, and set it before them; and he stood by them under the tree as they ate.
Then they said to him, “Where is Sarah your wife?”
So he said, “Here, in the tent.”
And He said, “I will certainly return to you according to the time of life, and behold, Sarah your wife shall have a son.”
(Sarah was listening in the tent door which was behind him.) Now Abraham and Sarah were old, well advanced in age; and Sarah had passed the age of childbearing. Therefore Sarah laughed within herself, saying, “After I have grown old, shall I have pleasure, my lord being old also?”
And the LORD said to Abraham, “Why did Sarah laugh, saying, ‘Shall I surely bear a child, since I am old?’ Is anything too hard for the LORD? At the appointed time I will return to you, according to the time of life, and Sarah shall have a son.”
But Sarah denied it, saying, “I did not laugh,” for she was afraid.
And He said, “No, but you did laugh!”
NKJV: New King James Version