New Defender's Study Bible Notes
13:21 because of the word. Unbelievers do not persecute believers because of their joyful feelings, but because of Christ and the Word. Emotional believers who have no grounding in the solid truth of the Word, and not knowing why they believe, cannot resist attacks of unbelievers (and of Satan) on their professed faith.
13:21 offended. Luke 8:13 adds that he will “fall away.”