Believing that they have eternal life enables God’s people to live well now (see 2:11–14; 3:7–8).
God, who cannot lie: The true God contrasts with popular Cretan ideas (see study note on 1:12). This statement also emphasizes God’s plan of salvation as unchanging (1:1): God can be trusted to fulfill his promises (see Numbers 23:19; 1 Samuel 15:29; Romans 3:3–4).