Tertullian

It does not matter that he also said, "For the destruction of the flesh, that the spirit may be saved in the day of the Lord," since both in the destruction of the flesh and in the saving of the spirit there is, on His part, judicial process; and when he bade "the wicked person be put away from the midst of them," he only mentioned what is a very frequently recurring sentence of the Creator. "Purge out the old leaven, that ye may be a new lump, as ye are unleavened." The unleavened bread was therefore, in the Creator's ordinance, a figure of us (Christians).

The unleavened bread was therefore, in the Creator's ordinance, a figure of us (Christians). "For even Christ our passover is sacrificed for us." But why is Christ our passover, if the passover be not a type of Christ, in the similitude of the blood which saves, and of the Lamb, which is Christ? Why does (the apostle) clothe us and Christ with symbols of the Creator's solemn rites, unless they had relation to ourselves? When, again, he warns us against fornication, he reveals the resurrection of the flesh.