Expositor's Bible Commentary Commentary 1 Thessalonians 4:5

"not in the passion of lust, even as the Gentiles who know not God;" — 1 Thessalonians 4:5 (ASV)

Those “who do not know God” (i.e., the “heathen” Gentiles; cf. Galatians 4:8; 2 Thessalonians 1:8; Jeremiah 10:25) know nothing of such holy and honorable behavior based on the law of Moses and the commands of Christ. Their guiding principle is “passionate lust.” Once removed from that realm into the church of God (cf. 1 Corinthians 10:32), believers are obligated to maintain much higher standards.