Titus 1:16

1:16 they deny him. The New Testament teaches that the lack of actions consistent with a changed life renders one’s faith in Christ suspect (Matt. 7:16–20; James 2:14–16; 1 John 3:17).

by their works. Paul condemns not only the doctrine of the false teachers, but also their actions (2 Tim. 3:2–5). Both sound doctrine and actions in accordance with a changed life are necessary for Christians.