Genesis 9:21-23

Young's Literal Translation

²¹ and drinketh of the wine, and is drunken, and uncovereth himself in the midst of the tent.

²² And Ham, father of Canaan, seeth the nakedness of his father, and declareth to his two brethren without.

²³ And Shem taketh -- Japheth also -- the garment, and they place on the shoulder of them both, and go backward, and cover the nakedness of their father; and their faces [are] backward, and their father's nakedness they have not seen.