Peter further calls his readers to increase in “knowledge” (γνῶσιν, gnōsin), a thematic word in the letter (see 1:6; 3:18) along with its cognate ἐπίγνωσις (epignōsis in 1:2–3, 8; 2:20). This is not theoretical knowledge or that of philosophy, which was frequently understood as the foundation of moral character (J. Charles 1997: 141). Nor is it esoteric knowledge of hidden mysteries (see “The Opponents in 2 Peter” in the introduction); rather, it is the personal knowledge of the Lord Jesus Christ