Exodus 12:15-17

Thomson(i) 15 Seven days you shall eat unleavened bread. And from the first day you shall remove all leaven out of your houses. Whoever shall eat leaven from the first to the seventh day, that soul shall be cut off from among Israel. 16 And with regard to the first day, it shall be proclaimed holy; and the seventh day shall be holy to you. In them you shall not do any kind of sacrificial service, save that which must be done for every soul. This alone shall be done for you 17 and you shall keep this commandment. For on that day I will lead out your host from the land of Egypt; therefore you shall make the observance of that day an everlasting rite to your generations.