FOURTH ARTICLE [I-II, Q. 106, Art. 4]
Whether the New Law Will Last Till the End of the World?
Objection 1: It would seem that the New Law will not last until the end of the world. Because, as the Apostle says (1 Cor. 13:10), “when that which is perfect is come, that which is in part shall be done away.” But the New Law is “in part,” since the Apostle says (1 Cor. 13:9): “We know in part and we prophesy in part.” Therefore the New Law is to be done away, and will be succeeded by a more perfect state.
Obj. 2: Further, Our Lord (John 16:13) promised His disciples the knowledge of all truth when the Holy Ghost, the Comforter, should come. But the Church knows not yet all truth in the state of the New Testament. Therefore we must look forward to another state, wherein all truth will be revealed by the Holy Ghost.
Obj. 3: Further, just as the Father is distinct from the Son and the Son from the Father, so is the Holy Ghost distinct from the Father and the Son. But there was a state corresponding with the Person of the Father, viz. the state of the Old Law, wherein men were intent on begetting children: and likewise there is a state corresponding to the Person of the Son: viz. the state of the New Law, wherein the clergy who are intent on wisdom (which is appropriated to the Son) hold a prominent place. Therefore there will be a third state corresponding to the Holy Ghost, wherein spiritual men will hold the first place.
Obj. 4: Further, Our Lord said (Matt. 24:14): “This Gospel of the kingdom shall be preached in the whole world . . . and then shall the consummation come.” But the Gospel of Christ is already preached throughout the whole world: and yet the consummation has not yet come. Therefore the Gospel of Christ is not the Gospel of the kingdom, but another Gospel, that of the Holy Ghost, is to come yet, like unto another Law.
On the contrary, Our Lord said (Matt. 24:34): “I say to you that this generation shall not pass till all (these) things be done”: which passage Chrysostom (Hom. lxxvii) explains as referring to “the generation of those that believe in Christ.” Therefore the state of those who believe in Christ will last until the consummation of the world.
I answer that, The state of the world may change in two ways. In one way, according to a change of law: and thus no other state will succeed this state of the New Law. Because the state of the New Law succeeded the state of the Old Law, as a more perfect law a less perfect one. Now no state of the present life can be more perfect that the state of the New Law: since nothing can approach nearer to the last end than that which is the immediate cause of our being brought to the last end. But the New Law does this: wherefore the Apostle says (Heb. 10:19-22): “Having therefore, brethren, a confidence in the entering into the Holies by the blood of Christ, a new . . . way which He hath dedicated for us . . . let us draw near.” Therefore no state of the present life can be more perfect than that of the New Law, since the nearer a thing is to the last end the more perfect it is.