‘But the firstling of an ass thou shalt redeem with a lamb: and if thou redeem him not, then shalt thou break his neck. All the firstborn of thy sons thou shalt redeem. And none shall appear before me empty.’—EXOD. xxxiv. 20. MAN is a very forgetful being, and there is nothing which he seems to forget so much as mercy. It takes a great deal to make us forget a trouble, but very little to wipe away the thought of mercy. Thus when God has wrought great acts He has not unfrequently appointed memorials in order to keep them in remembrance, and has provided for the failure of man’s memory by appointing something that may continually remind him of the past. Sometimes it has been a stone or monument, as, _e.g._ at the passage of Jordan, but more frequently it has been an institution, such as the Paschal Supper as a memorial of the Passover, and the Holy Communion, or the Supper of the Lord, in remembrance of His death and passion. These institutions have lasted much longer than the material monuments. The Paschal Supper lasted fifteen centuries, and the Lord’s Supper has already lasted more than eighteen. It seems a very simple institution. What can be more simple than to partake together of a little bread and wine in thankful remembrance of His death? But it has never been forgotten by the people of God, and never will be till the Advent. Wherever Christ has been preached this memorial feast has been observed. In all ages and all countries it has been the joy of God’s people. In all mission-stations as well as in our churches at home, always and everywhere, the sacred memorial has been reverently and lovingly observed by those who name the name of Jesus. But besides the Paschal Supper there was another institution ordained as a remembrance of the deliverance from Egypt. For as Israel was delivered through the death of the first-born of the Egyptians, it was established as a law in Israel that all their first-born both of man and beast should be given up to God. The law is given, and the reason of it, in Exod. xiii. In v. 2, we find the law, ‘Sanctify unto me all the first-born, whatsoever openeth the womb among the children of Israel, both of man and beast: it is mine;’ and in v. 14, the reason, ‘And it shall be, when thy son asketh thee in time to come saying, What is that? that thou shalt say to him, By strength of hand the Lord brought us out from Egypt from the house of bondage;’ and in the 16th verse we are taught that it was for a perpetual memorial before God, ‘And it shall be for a token upon thy hand, and for frontlets between thine eyes: for by strength of hand the Lord brought us out from Egypt.’