Accordingly the New Law had no other external works to determine, by prescribing or forbidding, except the sacraments, and those moral precepts which have a necessary connection with virtue, for instance, that one must not kill, or steal, and so forth.

Reply Obj. 1:  Matters of faith are above human reason, and so we cannot attain to them except through grace.  Consequently, when grace came to be bestowed more abundantly, the result was an increase in the number of explicit points of faith.  On the other hand, it is through human reason that we are directed to works of virtue, for it is the rule of human action, as stated above (Q. 19, A. 3; Q. 63, A. 2).  Wherefore in such matters as these there was no need for any precepts to be given besides the moral precepts of the Law, which proceed from the dictate of reason.

Reply Obj. 2:  In the sacraments of the New Law grace is bestowed, which cannot be received except through Christ:  consequently they had to be instituted by Him.  But in the sacred things no grace is given:  for instance, in the consecration of a temple, an altar or the like, or, again, in the celebration of feasts.  Wherefore Our Lord left the institution of such things to the discretion of the faithful, since they have not of themselves any necessary connection with inward grace.

Reply Obj. 3:  Our Lord gave the apostles those precepts not as ceremonial observances, but as moral statutes:  and they can be understood in two ways.  First, following Augustine (De Consensu Evang. 30), as being not commands but permissions.  For He permitted them to set forth to preach without scrip or stick, and so on, since they were empowered to accept their livelihood from those to whom they preached:  wherefore He goes on to say:  “For the laborer is worthy of his hire.”  Nor is it a sin, but a work of supererogation for a preacher to take means of livelihood with him, without accepting supplies from those to whom he preaches; as Paul did (1 Cor. 9:4, seqq.).

Secondly, according to the explanation of other holy men, they may be considered as temporal commands laid upon the apostles for the time during which they were sent to preach in Judea before Christ’s Passion.  For the disciples, being yet as little children under Christ’s care, needed to receive some special commands from Christ, such as all subjects receive from their superiors:  and especially so, since they were to be accustomed little by little to renounce the care of temporalities, so as to become fitted for the preaching of the Gospel throughout the whole world.  Nor must we wonder if He established certain fixed modes of life, as long as the state of the Old Law endured and the people had not as yet achieved the perfect liberty of the Spirit.  These statutes He abolished shortly before His Passion, as though the disciples had by their means become sufficiently practiced.  Hence He said (Luke 22:35, 36) “When I sent you without purse and scrip and shoes, did you want anything?  But they said:  Nothing.  Then said He unto them:  But now, he that hath a purse, let him take it, and likewise a scrip.”  Because the time of perfect liberty was already at hand, when they would be left entirely to their own judgment in matters not necessarily connected with virtue.