Leviticus 23:9-12

Then the LORD spoke to Moses, saying, “Speak to the sons of Israel and say to them, ‘When you enter the land which I am going to give to you and reap its harvest, then you shall bring in the sheaf of the first fruits of your harvest to the priest. He shall wave the sheaf before the LORD for you to be accepted; on the day after the sabbath the priest shall wave it. Now on the day when you wave the sheaf, you shall offer a male lamb one year old without defect for a burnt offering to the LORD.