Exodus 23:14-16

14Thrice in the year thou shalt celebrate a feast to me.

15Thou shalt keep the feast of unleavened bread, (thou shalt eat unleavened bread seven days, as I have commanded thee, in the time appointed of the month Abib; for in it thou camest out from Egypt; and none shall appear in my presence empty;)

16and the feast of harvest, the first-fruits of thy labours which thou hast sown in the field, and the feast of in-gathering, at the end of the year, when thou gatherest in thy labours out of the field.