Backslide
Easton’s Bible Dictionary
Backslide: to draw back or apostatize in matters of religion (Acts 21:21; 2 Thessalonians 2:3; 1 Timothy 4:1). This may be either partial (Proverbs 14:14) or complete (Hebrews 6:4-6; 10:38,39). The apostasy may be both doctrinal and moral.