Exodus 23:14-19 - Laws For Three Festivals
14 "Three feasts thou shalt hold unto me in a year. 15 Thou shalt keep the feast of sweet bread, that thou eat unleavened bread seven days long as I commanded thee in the time appointed of the month of Abib, for in that month thou camest out of Egypt: and see that no man appear before me empty. 16 And the feast of Harvest, when thou reapest the first fruits of thy labors which thou hast sown in the field. And the feast of ingathering, in the end of the year: when thou hast gathered in thy labors out of the field. 17 "Three times in a year shall all thy men children appear before the Lord Jehovah.
18 "Thou shalt not offer the blood of my sacrifice with leavened bread; neither shall the fat of my feast remain until the morning.
19 The first of the firstfruits of thy land thou shalt bring into the house of the LORD thy God. Thou shalt also not seethe a kid in his mother's milk.