Exodus 12:25-28King James Version (KJV)
25 And it shall come to pass, when ye be come to the land which the Lord will give you, according as he hath promised, that ye shall keep this service.
26 And it shall come to pass, when your children shall say unto you, What mean ye by this service?
27 That ye shall say, It is the sacrifice of the Lord's passover, who passed over the houses of the children of Israel in Egypt, when he smote the Egyptians, and delivered our houses. And the people bowed the head and worshipped.
28 And the children of Israel went away, and did as the Lord had commanded Moses and Aaron, so did they.