16. make you vain—They seduce you to vanity, that is, idolatry, which will prove a vain trust to you (Jer 2:5; 2Ki 17:15; Jon 2:8), [Gesenius]. Rather, "they delude you with vain promises of security" (Jer 23:17; compare Ps 62:10) [Maurer].
of their own heart—of their own invention (Jer 23:21; Jer 14:14).