But neither Titus. This is an additional argument to prove that the Apostles held the same views with himself; for he had brought to them an uncircumcised man, whom they did not hesitate to acknowledge as a brother. The reason is assigned why he was not circumcised; for circumcision, being a matter of indifference, might be neglected or practiced as edification required. Our invariable rule of action is, that, if "all things are lawful for us," (1-Corinthians 10:23) we ought to inquire what is expedient. He circumcises Timothy, (Acts 16:3,) in order to take away a ground of offense from weak minds; for he was at that time dealing with weak minds, which it was his duty to treat with tenderness. And he would gladly have done the same thing with Titus, for he was unwearied in his endeavors to "support (Acts 20:35) the weak;" but the case was different. For some false brethren were watching for an opportunity of slandering his doctrine, and would immediately have spread the report: "See how the valiant champion of liberty, when he comes into the presence of the apostles, lays aside the bold and fierce aspect which he is wont to assume among the ignorant!" Now, as it is our duty to "bear the infirmities of the weak," (Romans 15:1,) so concealed foes, who purposely watch for our liberty, must, be vigorously resisted. The duties of love to our neighbor ought never to be injurious to faith; and therefore, in matters of indifference, the love of our neighbour will be our best guide, provided that faith shall always receive our first regard.

But neither Titus, who was with me - Paul introduces this case of Titus undoubtedly to show that circumcision was not necessary for salvation. It was a case just in point. He had gone up to Jerusalem with the express reference to this question. Here was a man whom he had admitted to the Christian church without circumcising him. He claimed that he had a right to do so; and that circumcision was not necessary in order for salvation. If it were necessary, it would have been proper that Titus should have been compelled to submit to it. But Paul that says this was not demanded; or if demanded by anyone, the point was yielded, and he was not compelled to be circumcised. It is to be remembered that this was at Jerusalem; that it was a case submitted to the apostles there; and that consequently the determination of this case settled the whole controversy about the obligation of the Mosaic laws on the Gentile converts.
It is quite evident from the whole statement here that Paul did not intend that Titus should be circumcised; that he maintained that it was not necessary; and that he resisted it when it was demanded; Galatians 2:4-5. Yet on another occasion he himself performed the act of circumcision upon Timothy; Acts 16:3. But there is no inconsistency in Paul's conduct. In the case of Titus, it was demanded as a matter of right and as obligatory upon him, and Paul resisted the principle as dangerous. In the case of Timothy, it was a voluntary compliance on his part with the usual customs of the Jews, where it was not pressed as a matter of obligation, and where it would not be understood as indispensable to salvation. No danger would follow from compliance with the custom, and it might do much to conciliate the favor of the Jews, and he therefore submitted to it. Paul would not have hesitated to have circumcised Titus in the same circumstances in which it was done to Timothy; but the circumstances were different; and when it was insisted upon as a matter of principle and of obligation, it became a matter of principle and of obligation with him to oppose it.
Being a Greek - Born of Gentile parents, of course he had not been circumcised. Probably both his parents were Greeks. The case with Timothy was somewhat different. His mother was a Jewess, but his father was a Greek Acts 16:3.
Was compelled to be circumcised - I think it is implied here that this was demanded and insisted on by some that he should be circumcised. It is also implied that Paul resisted it, and the point was yielded, thus settling the great and important principle that it was not necessary in order for salvation; see Galatians 2:5.

But neither Titus, who was with me - The apostle proceeds to state that his account was so satisfactory to the apostles, that they not only did not require him to insist on the necessity of circumcision among the Gentiles, but did not even require him to have Titus, who was a Greek, circumcised; though that might have appeared expedient, especially at Jerusalem, to have prevented false brethren from making a handle of his uncircumcision, and turning it to the prejudice of the Gospel in Judea.
To spy out our liberty - The Judaizing brethren got introduced into the assembly of the apostles, in order to find out what was implied in the liberty of the Gospel, that they might know the better how to oppose St. Paul and his fellows in their preaching Christ to the Gentiles, and admitting them into the Church without obliging them to observe circumcision and keep the law. The apostle saw that while such men were in the assembly it was better not to mention his mission among the Gentiles, lest, by means of those false brethren, occasion should be given to altercations and disputes; therefore he took the opportunity, by private conferences, to set the whole matter, relative to his work among the Gentiles, before the chief of the apostles.

But neither Titus, who was with me, being a Greek,.... There was such an agreement between the apostle, and his fellow apostles at Jerusalem, even about this article of the necessity of circumcision, and other rituals of the law of Moses, to salvation; that Titus, whom he brought along with him, an intimate companion of his in his travels, a fellow labourer with him in the ministry, and now upon the spot, though he was a Gentile, an uncircumcised person, yet even not he
was compelled to be circumcised: the elders did not urge it, or insist upon it, as proper and necessary; they looked upon it as a thing indifferent, left him to his liberty, and made use of no forcible methods to oblige him to it; yea, were of opinion, as Peter and James in the synod declared, that such a yoke ought not to be put upon the necks of the disciples, and that those who turned to God from among the Gentiles, should not be troubled with these things.

But--So far were they from regarding me as running in vain, that "not even Titus who was with me, who was a Greek (and therefore uncircumcised), was compelled to be circumcised." So the Greek should be translated. The "false brethren," Galatians 2:4 ("certain of the sect of the Pharisees which believed," Acts 15:5), demanded his circumcision. The apostles, however, constrained by the firmness of Paul and Barnabas (Galatians 2:5), did not compel or insist on his being circumcised. Thus they virtually sanctioned Paul's course among the Gentiles and admitted his independence as an apostle: the point he desires to set forth to the Galatians. Timothy, on the other hand, as being a proselyte of the gate, and son of a Jewess (Acts 16:1), he circumcised (Acts 16:3). Christianity did not interfere with Jewish usages, regarded merely as social ordinances, though no longer having their religious significance, in the case of Jews and proselytes, while the Jewish polity and temple still stood; after the overthrow of the latter, those usages naturally ceased. To have insisted on Jewish usages for Gentile converts, would have been to make them essential parts of Christianity. To have rudely violated them at first in the case of Jews, would have been inconsistent with that charity which (in matters indifferent) is made all things to all men, that by all means it may win some (1-Corinthians 9:22; compare Romans 14:1-7, Romans 14:13-23). Paul brought Titus about with him as a living example of the power of the Gospel upon the uncircumcised heathen.

But neither was Titus who was with me - When I conversed with them. Compelled to be circumcised - A clear proof that none of the apostles insisted on the circumcising gentile believers. The sense is, And it is true, some of those false brethren would fain have compelled Titus to be circumcised; but I utterly refused it.