Ver. 25-26. I would not have you ignorant, brethren, of this mystery, this hidden truth of God’s justice and mercy, that blindness in part hath happened in Israel, or to part of them, until the fulness of the Gentiles should come in, by the conversion of all nations: and then all Israel should be saved, when they shall submit to the faith of Christ: as it is written by the prophet Isaias, (lix. 20.) there shall come out of Sion he that shall deliver; that is, their Redeemer, Christ Jesus, who is indeed come already, but who shall then come to them by his powerful grace. This is my covenant with them. (Witham)

For I would not have you ignorant, brethren, of this mystery, (lest you should be wise in your own conceits), that blindness in part has happened in Israel, until the fulness of the Gentiles should come in. - Romans 11:25

After leading the Gentiles to a knowledge of the divine judgments, in which God's kindness and severity were manifested, the Apostle, acting as though they are still unable to consider these things, explains how they seem to him. First, he presents the fact; secondly, he proves it [v. 26b; n. 917]; 453 thirdly, he gives the reason [v. 30; n. 930]. 913. In regard to the first he does three things. First, he states his intention, saying: IO have urged you to consider the kindness and severity of God, because I want you to understand this mystery, for you cannot grasp all mysteries. Hence, this is a prerogative of the perfect to whom the Lord say: "To you it has been given to understand the mystery of God's kingdom: (Lk 8:9); "I will not hide from you the mysteries of God" (Wis 6:24). But ignorance of this mystery would be very damaging to us. 914. Secondly, he discloses the reason for his intention: that you not be wise in your own conceits, i.e., not presume on your own understanding to condemn others and prefer yourself to them: "Never be conceited" (Rom 1:16); "Woe to those who are wise in their own eyes, and shrewd in their own sight (Is 5:21). 915. Thirdly, he states what he intended. First, with respect to the fall of particular Jєωs, when he says: a hardening has come upon Israel, not universally but upon a part: "Blind the heart of this people" (Is 6:10). Secondly, he predicts the end of this blindness, saying: until the full number of the Gentiles come in to the faith, i.e., not only some Gentile nations as were then converted; but either in all or the greater part the Church would be establishes: "The earth is the Lord's and all its fullness" (Ps 23:1). The Gentiles converted to the faith are said to come in, as though from the exterior and visible things they venerated into spiritual things and the divine will: "Come into his presence with singing" (Ps 100:2). 454 916. It should be noted that the word, until, can signify the cause of the blindness of the Jєωs. For God permitted them to be blinded, in order that the full number of the Gentiles come in. It can also designate the termination, i.e., that the blindness of the Jєωs will last up to the time when the full number of the Gentiles will come to the faith. With this agrees his next statement, namely, and then, i.e., when the full number of the Gentiles has come in, all Israel will be saved, not some, as now, but universally all: "I will save them by the Lord their God" (Hos 1:7); "He will again have compassion upon us (Mic 7:19). 917. Then when he says, As it is written, he proves what he had said about the future salvation of the Jєωs: first, he proves this with an authority; secondly, with a reason [v. 28; n. 921]. 918. First, therefore, he says: I say that all Israel will be saved, as it is written in Is (59:20), where our text says: "A redeemer will come from Zion and this will be my covenant with them that return to Jacob says the Lord." But the Apostle uses the Septuagint and touches on three things. First, the coming of a Savior, when he says: God will come, in human flesh to save us, from Zion, i.e., from the Jєωιѕн people who are signified by Zion, the citadel of Jerusalem, a city in Judea. Hence it says in Zech (9:9): " Rejoice greatly, o daughter of Zion! Shout aloud, O daughter of Jerusalem! Lo, our king comes to you..." and in Jn (4:22): "Salvation is from the Jєωs." 455 Or he says that he comes from Zion, not because he was born there, but because his doctrine went from there into the whole world, inasmuch as the apostles received the Holy Spirit in the cenacle in Zion: "Out of Zion shall go forth the law" (Is 2:3). 919. Secondly, he touches on salvation by Christ offered to the Jєωs, saying: he will banish ungodliness from Jacob. This could refer to deliverance from punishment: "He will snatch my soul from death" (Ps 115:8). Banish ungodliness from Jacob could refer to deliverance from guilt: "O that deliverance for Israel would come from Zion" (Ps 53:6). Or both could refer to liberation from guilt, but he says he will take out, because of the few, who now are converted with great difficulty and with, so to speak, a certain violence: "As if a shepherd should get out of the lion's mouth two legs, or the tip of the ear, so shall the children of Israel be taken out" (Amos 3:12). But he says will banish ungodliness from Jacob to show the ease with which the Jєωs will be converted at the end of the world: "Who is a God like thee, pardoning iniquity and passing over transgression for the remnant of his inheritance?" (Mic 7:18). 920. Thirdly, he shows the manner of salvation when hey says: And this will be my covenant with them, a new one from me, when I take away their sins. For the old covenant did not remove sins, because "it is impossible that the blood of bulls and goats should take away sins" (Heb 10:4). Therefore, because the Old Testament was imperfect, a new testament is promised to them: "I will make a new covenant with the house of Israel and the house of Judah" (Jer 31:31) and it will have the power to remit sin through the blood of Christ: "This is my blood of the new covenant, which is poured out for many 456 for the forgiveness of sins" (Mt 26:28); "He will cast all our sins into the depths of the sea" (Mic 7:19). 921. Then when he says, As regards the gospel, he proves his statement with a reason: first, he presents the proof; secondly, he removes an objection [v. 29; n. 924]. 922. First, therefore, he says that their sins will be taken away and that after they have sins, they are enemies of Christ. As regards the gospel, which they resist, they are enemies for your sake, i.e., it has turned out to your benefit. Hence, it says in Lk (19:27): "As for those enemies of mind, who did not want me to reign over them, bring them here and slay them before me"; and in Jn (15:24): "But now they have seen and hated both me and my Father." Or as regards the gospel means their enmity has helped the gospel, which has been spread everywhere by reason of such enmity: "In the word of truth of the gospel, which has come to you, as indeed in the whole world it is bearing fruit and growing" (Col 1:5). 923. But they are beloved by God for the sake of their forefathers as regards election, because He chose their descendants on account of their forefathers' grace: "The Lord loved your fathers and chose their descendants after them" (Dt 10:15). This does not means that the merits established by the fathers were the cause of the eternal election of the descendants, but that God from all eternity chose the fathers and the sons in such a way that the children would obtain salvation on account of the fathers; not as though the merits of the fathers were sufficient for the salvation of the 457 sons, but through an outpouring of divine grace and mercy, the sons would be saved on account of the promises made to the fathers. Or it can mean as regards election, i.e., as regards those elected from that people, salvation was obtained. For if they are dear to God, it is reasonable that they be saved by God: "The eye hath not seen, O God, besides thee, what things thou has prepared for them that wait for thee" (Is 64:4). 924. Then when he says, For the gifts, he excludes an objection. For someone might claim that even though the Jєωs were formerly beloved on account of their forefathers, nevertheless the hostility they exert against the gospel prevents them from being saved in the future. But the Apostle asserts that this is false, saying: The gifts and call o God are irrevocable, i.e., without repentance. As if to say: That God gives something to certain ones or call certain ones is without repentance, because God does not change His mind: "The Lord has sworn and will not change his mind" (Ps 110:4). 925. However, this seems false, for the Lord says: "It repenteth me that I made man" (Gen 6:7) and "if that nation against which I have spoken shall repent of their evil, I also will repent of the evil that I thought to do to them" (Jer 18:8). The answer is that just as God is said to grow angry, not because the emotion of anger is in him but because he is related to the effect of punishments after the manner of an angry man, so he is said to repent, not because the change involved in repentance is in him but because he changes what he had done after the manner of one who repents. 926. Nevertheless, it does seem that God's gifts are not without repentance, because they are frequently lost, as in Mt (25:28): "Take the talent from him and give it 458 to him that has ten talents." Furthermore, God's call seems to be changed sometimes, since it is written: "Many are called but few are chosen" (Mt 22:14). But it should be noted that "gift" is taken here for a promise made according to God's foreknowledge or predestination, and "call" is taken for election. Because both are so certain, whatever God promises is as good as given and whomever He elects is somehow already called. Such temporal gifts and callings are not voided by a change in God, as though He repented of them, but by a change in man who casts them off: "Take heed lest anyone be wanting in the grace of God" (Heb 12:15). 927. This passage can also be taken to mean that God's gifts which are bestowed in baptism, and the calling by which the baptized person is called, exist without the repentance of the baptized person. Furthermore, it was introduced to counteract any despair about the future salvation of the Jєωs, since they do not seem to repent of their sin. But against this interpretation are the words of Peter: "Repent and be baptized everyone of you" (Ac 2:38). This can be answered by recalling that repentance is of two kinds: interior and exterior. Interior repentance consists in the heart's contrition by which one is sorry for past sins. Such repentance is required of the baptized, because, as Augustine says: "No one who is arbiter of his own will can begin the new life, unless he repents of the old life; otherwise, he would approach dissembling." But exterior repentance consists in making satisfaction outwardly, and this is not required of the baptized person, because by baptismal grace man is freed not only of guilt but of all penalty, in virtue of the passion of Christ who satisfied for the sins of all: "All 459 of us who have been baptized into Jesus Christ were baptized into his death" (Rom 6:3); "By the washing of regeneration and renewal in the Holy Spirit which he poured out upon us richly through Jesus Christ" (*** 3:5). 928. But since the keys of the Church and all the other sacraments work by the power of Christ’s passion, it seems that by the same reasoning all the other sacraments should liberate man from guilt and from all punishment. But the answer is that Christ’s passion works in baptism in the manner of a generation, which requires that a man die completely to his former life to receive a new life. And because the debt of punishment belongs to the oldness of the former life, it is taken away in baptism. But in the other sacraments Christ’s passion works in the manner of a cleansing, as in the sacrament of penance. But a cleansing does not require that right away every remnant of weakness be taken away. And the same argument applies to the other sacraments. 929. But since the confession of sins is relevant for exterior repentance, one could ask whether confession of sins is required at baptism. And it seems that it is, because Mt 3(:6) says that men were baptized by John, "confessing their sins." But the answer is that John’s baptism was a baptism of repentance, namely because by receiving that baptism they declared that they would undertake penance for their sins, and so it was fitting that they should confess so that penance could be meted out to them in accord with the nature of their sins. But Christ’s baptism is a baptism for the remission of all sins, such that the baptized person no longer owes any satisfaction for his past sins, and for this reason there is no need for vocal confession. For the reason 460 confession is necessary on the sacrament of penance is so that the priest can, by the power of the keys, fittingly loose or bind the penitent. 930. Then when he says, Just as you were, he gives the reason for the future salvation of the Jєωs after their unbelief. First, he shows a similarity between the salvation of both people; secondly, the cause of this similarity [v. 32; n. 932]. 931. First, therefore, he says: So I say that Israel will be saved, although they are now enemies. For just as you Gentiles once did not believe God: "You were once without God in the world" (Eph 2:12); but now have received mercy because of their unbelief: below (15:9), "The Gentiles are to honor God for his mercy"; "I will have mercy on him who was without mercy" (Hos 2:23). And this was because of their unbelief, which was the occasion of your salvation, as was said above. So they, i.e., the Jєωs, now, i.e., in the time of grace, have not believed, namely, Christ: "Why do you not believe me?" (Jn 8:46). And this is what he adds: In order that by the mercy shown to you, i.e., in Christ's grace, by which you have obtained mercy: "You have saved us according to your mercy" (*** 3:5). Or they have not believed so that they enter into your mercy. Or they have not believed, which turned out to be the occasion of the mercy shown to you, in order that they also at some time may receive mercy: "The Lord will have compassion on Jacob" (Is 14:1). 932. Then when he says, For God, he gives the reason for this similarity, namely, because God wills that His mercy find room in all. And this is what he says: For God has included, i.e., allowed to be included, all, i.e., every race of men, both Jєωs and Gentiles, in unbelief, as in a chain of error: "They were all bound together with one chain of 461 darkness" (Wis 17:17), that he may have mercy on us, i.e., that His mercy find a place in every race of men. This should not be extended to included demons, as Origen would, or even to all men individually, but to all races of men. The statement applies to the genera of individuals not to all the individuals of the genera. God wishes all men to be saved by His mercy, in order that they be humbled by this fact and ascribe their salvation not to themselves but to God: "Destruction is thy own, O Israel: they help is only in me" (Hos 13:9); "In order that every mouth may be stopped, and the whole world may be made subject to God" (Rom 3:19).

- Thomas Aquinas

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So Jesus comes first and then the Jєωs convert ?

Sorry, it's quite heavy going and I'm autistic

Is there a cut of point for gentiles then ? If only Jєωs can convert?