Genesis 7:2-5

Of every clean beast thou shalt take to thee by sevens, the male and his female: and of beasts that {are} not clean by two, the male and his female. {by sevens: Heb. seven seven} Of fowls also of the air by sevens, the male and the female; to keep seed alive upon the face of all the earth. {by sevens: Heb. seven seven} For yet seven days, and I will cause it to rain upon the earth forty days and forty nights; and every living substance that I have made will I destroy from off the face of the earth. {destroy: Heb. blot out} And Noah did according unto all that the LORD commanded him.