Haydock Catholic Bible Commentary
Be not held again under the yoke of bondage, of the old law. (Witham) --- This verse must be understood in the same manner as the 9th verse of the preceding chapter. See the annotations upon it.
If you converted from heathenism be circumcised, it must be by believing and professing it necessary, which is false doctrine, and the Christ will profit you nothing: not that the practice of those ceremonies was at the time sinful, especially for those that had been Jews, but it was an error to judge them necessary for converted Gentiles. Besides, he that judges circumcision necessary, must also judge himself bound to keep all the other ceremonies and precepts of the law. (Witham)
Gal 5:3 false teachers had insisted on the observance of circumcision and a few other rites only, as necessary for salvation; but St. Paul assures them, that the receiving of circumcision is an open profession of Judaism, and that he that makes this profession, binds himself to the observance of every part of the law, since a curse is pronounced against those that do not keep it in all its parts. If then circumcision be necessary for salvation, the whole law is necessary also. (Calmet)
Gal 5:4 you think that justice cannot be obtained but under the law, you make a renunciation of the justice of Christ: his mediation becomes of no avail to you. (Calmet)
We in spirit hope for true justice by faith in Christ; yet not by faith only, but by faith working by charity. (Witham) --- Here note with St. Augustine, that faith is not to be idle, but working or doing good works in charity: wherefore not faith alone. (De opere et fide. chap. xiv.)
This persuasion of yours is not from him who calleth you; is not from God: and I hope you will be shortly again of no other mind than what I taught you. (Witham) --- This was a Jewish proverb, and alluded to the time of the Pasch, when it was not permitted to eat of any but unleavened bread; during which time the least leaven made the whole mass unclean to a Jew....Some Greek copies read, Greek: mikra zume olon to phurama zumoi, when the sense will be, "a little leaven causes the whole mass to rise." (Calmet) --- Hence the introduction of any, however small, share of the ceremonial and Jewish rites, will greatly disfigure the purity and simplicity of the Christian institute. --- As for me, my adversaries misrepresent me, when they say I preach circumcision; which if I did, I should not be persecuted as I am by the Jews. I never preach it necessary for Gentile converts, though I have not condemned the use of it for the Jewish converts, provided they do not oblige other converts to it. --- The scandal of the cross is therefore made void. The sense is, according to St. Jerome, that the Jews' greatest objection against St. Paul used to be, because he preached that circumcision and the law of Moses need not be observed: another objection against him was, that he preached Jesus, who was crucified on an infamous cross, to be their great Messias. He reasons then in this manner, that if the Jews think he again preacheth the necessity of circumcision and the precepts of the old law, they will no longer be offended that he preacheth Christ crucified, because they were not so much offended with the latter as with the first. Thus also St. John Chrysostom on this verse. Others expound it thus: If I preach circumcision and the ceremonies of the law, therefore according to my doctrine, the cross of Christ, and justification by the merits of Christ crucified, is abolished, because justification is still to be sought for by the works of the law. --- I would they were even cut off: separated from your communion by excommunication. This seems the true sense; so that I need not mention any other exposition. See Corn. a Lapide. (Witham)
An occasion to the flesh; i.e. that you abuse not, by a vicious life, that Christian liberty which Christ hath purchased for you, but be united in the spirit of charity. (Witham)
Gal 5:14 the law, as far as it regards our duty to our neighbour, is contained in this text of the apostle; he says the same in his epistle to the Romans, Chap. xiii. He that loves his neighbour has fulfilled the law.
So that you  do not the things that you would. He does not say, so that you cannot do, as others falsely translate; as if men were under an absolute necessity of sinning, or doing ill; which is also contradictory to the foregoing words, walk by the spirit, and you will not accomplish the works of the flesh. (Witham) --- Here some suppose, says St. Augustine, that the apostle denieth that we have free liberty of will: not understanding that this is said to them, if they will not hold fast the grace of faith conceived, by which only they can walk in the spirit, and not accomplish the lusts of the flesh. (St. Augustine, in chap. v. Gal.)
Ver 19-21. Uncleanness, immodesty, luxury. In the Greek there are but two vices named; luxury is not mentioned; and, perhaps, the Latin interpreter put two words to explain one Greek word. (Witham) --- St. Augustine here sheweth that there are other damnable sins besides infidelity.
Ita ut non quæcunque vultis, illa faciatis; Greek: ina me a an thelete tauta poiete. Dr. Wells, in his correction to the Protestant translation, leaves out cannot.
The fruit of the Spirit is charity, &c. There are numbered twelve of these fruits in the Latin, though but nine in the Greek text, in St. John Chrysostom; St. Jerome; St. Augustine, tract. lxxxvii. in Joan. p. 756. The difference may again happen by the Latin interpreter using two words to express one Greek word. It is observed, that longanimity and patience are in a manner the same; so are benignity and goodness; and so may be here continency and chastity. (Witham)