The necessity for keeping their communion pure, for being a society with no leaven of wickedness among them, Paul proceeds to urge and illustrate in the words, "For even Christ our passover is sacrificed for us; therefore let us purge out the old leaven." The allusion was, of course, much more telling to Jews than it can possibly be to us; still, if we call to mind the outstanding ideas of the Passover, we cannot fail to feel the force of the admonition. That must be the simplest explanation of the Passover which Jewish parents were enjoined to give to their children, in the words, "By strength of hand the Lord brought us out of Egypt, from the house of bondage. And it came to pass when Pharaoh would hardly let us go, that the Lord slew all the firstborn in the land of Egypt, with the firstborn of man and the firstborn of beast. Therefore I sacrifice to the Lord all the firstborn being males, but all the firstborn of my children I redeem." That is to say, all the firstborn of animals they sacrificed to God, slaying them on His altar, but instead of slaying the human firstborns they redeemed them by sacrificing a lamb in their stead. The whole transaction of the night of the first Passover stood thus: God claimed the Israelites as His people; the Egyptians also claimed them as theirs. And as no warning would persuade the Egyptians to let them away to serve God, God at last forcibly delivered them, slaying the flower of the Egyptian people, and so crippling and dismaying them as to give Israel opportunity of escape. Being thus rescued that they might be God's people, they felt bound to continue to own this; and in accordance with the custom of their time they expressed their sense of it by sacrificing their firstborn, by presenting them to God as belonging to Him. By this outward sacrificial act engaged in by every family it was acknowledged that the whole nation belonged to God. Christ, then, is our Passover or Paschal Lamb, in the first place, because through Him there is made the acknowledgment that we belong to God. He is in very truth the prime and flower, the best representative of our race, the firstborn of every creature. He is the one who can make for all others this acknowledgment that we are God's people. And He does so by perfectly giving Himself up to God. This fact that we belong to God, that we men are His creatures and subjects, has never been perfectly acknowledged save by Christ. No individual or society of people has ever lived entirely for God. No man has ever fully recognised this apparently simple truth, that we are not our own, but God's. The Israelites made the acknowledgment in form, by sacrifice, but Christ alone made it in deed by giving Himself up wholly to do God's will. The Israelites made the acknowledgment from time to time, and with probably more or less truthfulness and sincerity, but Christ's whole spirit and habitual temper of mind was that of perfect obedience and dedication.