For whoremongers, for them that defile themselves with mankind, for menstealers, for liars, for perjured persons, and if there be any other thing that is contrary to sound doctrine;

People's New Testament

1:10 Kidnappers. Those who stole men and sold them into slavery.

Contrary to sound doctrine. Everything is forbidden which is opposed to the gospel.

Wesley's Notes

1:10 Manstealers - The worst of all thieves, in comparison of whom, highwaymen and housebreakers are innocent. What then are most traders in negroes, procurers of servants for America, and all who list soldiers by lies, tricks, or enticements?

Jamieson-Fausset-Brown Bible Commentary

10. whoremongers, &c.-sinners against the seventh commandment.

men-stealers-that is, slave dealers. The most heinous offense against the eighth commandment. No stealing of a man's goods can equal in atrocity the stealing of a man's liberty. Slavery is not directly assailed in the New Testament; to have done so would have been to revolutionize violently the existing order of things. But Christianity teaches principles sure to undermine, and at last overthrow it, wherever Christianity has had its natural development (Mt 7:12).

liars . perjured-offenders against the ninth commandment.

if there be any other thing-answering to the tenth commandment in its widest aspect. He does not particularly specify it because his object is to bring out the grosser forms of transgression; whereas the tenth is deeply spiritual, so much so indeed, that it was by it that the sense of sin, in its subtlest form of "lust," Paul tells us (Ro 7:7), was brought home to his own conscience. Thus, Paul argues, these would-be teachers of the law, while boasting of a higher perfection through it, really bring themselves down from the Gospel elevation to the level of the grossly "lawless," for whom, not for Gospel believers, the law was designed. And in actual practice the greatest sticklers for the law as the means of moral perfection, as in this case, are those ultimately liable to fall utterly from the morality of the law. Gospel grace is the only true means of sanctification as well as of justification.

sound-healthy, spiritually wholesome (1Ti 6:3; 2Ti 1:13; Tit 1:13; 2:2), as opposed to sickly, morbid (as the Greek of "doting" means, 1Ti 6:4), and "canker" (2Ti 2:17). "The doctrine," or "teaching, which is according to godliness" (1Ti 6:3).

Matthew Henry's Concise Commentary

1:5-11 Whatever tends to weaken love to God, or love to the brethren, tends to defeat the end of the commandment. The design of the gospel is answered, when sinners, through repentance towards God and faith in Jesus Christ, are brought to exercise Christian love. And as believers were righteous persons in God's appointed way, the law was not against them. But unless we are made righteous by faith in Christ, really repenting and forsaking sin, we are yet under the curse of the law, even according to the gospel of the blessed God, and are unfit to share the holy happiness of heaven.