John Stott writes,
The devil disturbs the church as much by error as by evil. When he cannot entice Christian people into sin, he deceives them with false doctrine. (The Message of Galatians, 24)
One of the chief ways the devil entices Christians is by tempting them to mingle their own morality with the gospel. What God has done in Jesus remains wonderful, but not quite enough. This is demonic, and any kind of doctrine that asserts any version of this is anathema.
Whenever teachers start exalting man, implying that he can contribute anything to his salvation by his own morality, religion, philosophy, or respectability, the gospel of grace is being corrupted. (p. 27)
Jesus is enough. Don’t let the devil disturb you into thinking that Jesus’ perfect work needs the assistance of your works. If temptation to sin is not an effective way for the devil to trip you up, he will use your not tripping up to tempt you with pride.
When the devil disturbs you with either of these, disturb him with the perfect work of Jesus on your behalf that has conquered him.