Of God (ek tou theou). See 1Jo 3:10; 1Jo 4:6 for this idiom.
Lieth in the evil one (en tōi ponērōi keitai). Present middle indicative of the defective verb keimai, to lie, as in Luk 2:12. Ponērōi is masculine, like ho ponēros in 1Jo 5:18. This is a terrible picture of the Graeco-Roman world of the first century a.d., which is confirmed by Paul in Romans 1 and 2 and by Horace, Seneca, Juvenal, Tacitus.