In the original institution it was specially enjoined that the history and purpose of this great festival should _be made known to their children_. “And thou shalt _show thy son_ in that day, saying, This is done because of that which the Lord did unto me when I came forth out of Egypt” (Ex. 13: 7). “And it shall be when thy son asketh thee in time to come, saying, What is this? that thou shalt say unto him, By strength of hand the Lord brought us out from Egypt, from the house of bondage,” etc. (Ex. 13: 14, 15.) How naturally would this wonderful story thrill the young hearts around the paschal board! How swiftly would the hours fly away while fathers rehearsed to sons the great national traditions, or read from the book of the law the narrative, and sung again and again the song of triumph over Pharaoh fallen with which this story closes! Jewish history has it that in ancient times it became the custom, after the paschal table was fully spread and the family had taken their places about it, for the servant suddenly to remove the prepared food away. Then when the hungry children opened their eyes wide and eager lips cried out――What does this mean? the head of the household rehearsed slowly and solemnly the meaning and purpose of the feast, with the history of its original institution; then when the curiosity of the little ones had been both aroused and enlightened, the provisions were replaced and partaken with a freshened sense of the grand significance of the Passover. Closely associated with this festival and fraught with solemn significance as a memorial institution was the _consecration to God of all first-born males_, both the first-born of man and the first-born of beast (Ex. 13: 11–16). Of the lower animals the first-born males, if without blemish and if suitable for sacrifice, were to be offered in sacrifice to the Lord. If not suitable (_e. g._ the ass), it must be redeemed with a lamb――in which case the lamb became the sacrifice, and the ass might be used at the pleasure of its owner. In the family, the first-born son was consecrated to God. In carrying out this principle, a substitution was made by which the entire tribe of Levi were put in the place of all the first-born males of Israel and held to be specially consecrated to God. The language (Num. 8: 14–18) is――“Thou shalt separate the Levites from among the children of Israel, and the Levites shall be mine. They are wholly given unto me from among the children of Israel, instead of such as open every womb, even instead of the first-born of all the children of Israel, have I taken them unto me. For all the first-born of Israel are mine both man and beast: on the day that I smote every first-born in the land of Egypt, I sanctified them for myself. And I have taken the Levites _for_ [in the place of] all the first-born of the children of Israel.”――――The law prescribed the rites by which the Levites were set apart (Num. 8: 5–15).