Leviticus 22:27

God spoke to Moses: “When a calf or lamb or goat is born, it is to stay with its mother for seven days. After the eighth day, it is acceptable as an offering, a gift to God. Don’t slaughter both a cow or ewe and its young on the same day. When you sacrifice a Thanksgiving-Offering to God, do it right so it will be acceptable. Eat it on the same day; don’t leave any leftovers until morning. I am God.