They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate.

People's New Testament

Titus 1:16 They profess that they know God. These teachers of Jewish fables and carnal ordinances profess to know and serve God, yet their immoral lives are a denial of him.

King James Translators' Notes

reprobate: or, void of judgment

Jamieson-Fausset-Brown Bible Commentary

16. They profess-that is, make a profession acknowledging God. He does not deny their theoretical knowledge of God, but that they practically know Him.

deny him-the opposite of the previous "profess" or "confess" Him (1Ti 5:8; 2Ti 2:12; 3:5).

abominable-themselves, though laying so much stress on the contracting of abomination from outward things (compare Le 11:10-13; Ro 2:22).

disobedient-to God (Tit 3:3; Eph 2:2; 5:6).

reprobate-rejected as worthless when tested (see on [2525]Ro 1:28; [2526]1Co 9:27; [2527]2Ti 3:8).

Matthew Henry's Concise Commentary

1:10-16 False teachers are described. Faithful ministers must oppose such in good time, that their folly being made manifest, they may go no further They had a base end in what they did; serving a worldly interest under pretence of religion: for the love of money is the root of all evil. Such should be resisted, and put to shame, by sound doctrine from the Scriptures. Shameful actions, the reproach of heathens, should be far from Christians; falsehood and lying, envious craft and cruelty, brutal and sensual practices, and idleness and sloth, are sins condemned even by the light of nature. But Christian meekness is as far from cowardly passing over sin and error, as from anger and impatience. And though there may be national differences of character, yet the heart of man in every age and place is deceitful and desperately wicked. But the sharpest reproofs must aim at the good of the reproved; and soundness in the faith is most desirable and necessary. To those who are defiled and unbelieving, nothing is pure; they abuse, and turn things lawful and good into sin. Many profess to know God, yet in their lives deny and reject him. See the miserable state of hypocrites, such as have a form of godliness, but are without the power; yet let us not be so ready to fix this charge on others, as careful that it does not apply to ourselves.