On the contrary, It is written (Lev. 20:8):  “I am the Lord that sanctify you.”  But nothing unreasonable is done by God, for it is written (Ps. 103:24):  “Thou hast made all things in wisdom.”  Therefore there was nothing without a reasonable cause in the sacraments of the Old Law, which were ordained to the sanctification of man.

I answer that, As stated above (Q. 101, A. 4), the sacraments are, properly speaking, things applied to the worshippers of God for their consecration so as, in some way, to depute them to the worship of God.  Now the worship of God belonged in a general way to the whole people; but in a special way, it belonged to the priests and Levites, who were the ministers of divine worship.  Consequently, in these sacraments of the Old Law, certain things concerned the whole people in general; while others belonged to the ministers.

In regard to both, three things were necessary.  The first was to be established in the state of worshipping God:  and this institution was brought about—­for all in general, by circumcision, without which no one was admitted to any of the legal observances—­and for the priests, by their consecration.  The second thing required was the use of those things that pertain to divine worship.  And thus, as to the people, there was the partaking of the paschal banquet, to which no uncircumcised man was admitted, as is clear from Ex. 12:43, seqq.:  and, as to the priests, the offering of the victims, and the eating of the loaves of proposition and of other things that were allotted to the use of the priests.  The third thing required was the removal of all impediments to divine worship, viz. of uncleannesses.  And then, as to the people, certain purifications were instituted for the removal of certain external uncleannesses; and also expiations from sins; while, as to the priests and Levites, the washing of hands and feet and the shaving of the hair were instituted.

And all these things had reasonable causes, both literal, in so far as they were ordained to the worship of God for the time being, and figurative, in so far as they were ordained to foreshadow Christ:  as we shall see by taking them one by one.

Reply Obj. 1:  The chief literal reason for circumcision was in order that man might profess his belief in one God.  And because Abraham was the first to sever himself from the infidels, by going out from his house and kindred, for this reason he was the first to receive circumcision.  This reason is set forth by the Apostle (Rom. 4:9, seqq.) thus:  “He received the sign of circumcision, a seal of the justice of the faith which he had, being uncircumcised”; because, to wit, we are told that “unto Abraham faith was reputed to justice,” for the reason that “against hope he believed in hope,” i.e. against the hope that is of nature he believed in the hope that is of grace, “that he might be made the father of many nations,” when he