John now called on his readers to abide in the true doctrine of Jesus Christ to enable them to abide in fellowship with God.
2:24 Christians should not reject the truth that they believed that resulted in their salvation (cf. the warning passages in Hebrews). Such faithfulness enables us to continue to abide in fellowship with God. John used "abide"in the same sense in which Jesus did in the Upper Room Discourse. Abiding refers to an intimate relationship with God determined by the extent to which we walk in the light of God's will that we have. Abiding, fellowship, and knowing God refer to the same thing, and we experience them by degrees rather than either completely or not at all (John 15:1-8). John's insistence that his readers really did know God and His truth would have strengthened them to resist the false teachers (vv. 12-14, 21).
2:25 Our eternal life is not in question when we believe that Jesus is the Savior, as some of the antichrists then and now suggest that it is. It is secure because it rests on God's promise, "He who believes on the Son has life"(John 3:36; et al.).98
