Read 1 John 5:3-12. Why does the apostle John limit “eternal life” only to those who are in Christ?

 The biblical doctrine of conditional immortality of the human being — in contrast to the nonbiblical theory of the natural immortality of the soul — is made explicit in 1 John 5:11, 12. To grasp the meaning of this significant passage, we have to remember that only the Godhead “has immortality” (1 Tim. 6:15, 16, NKJV) and is the only Source of life (Ps. 36:9, Col. 1:15-17, Heb. 1:2).

 When sin entered the world through the fall of Adam and Eve (Genesis 3), they and all their descendants (including us) came under the curse of physical death and lost the gift of eternal life. But our loving God implemented the plan of salvation for human beings to regain eternal life, the life that was to have been theirs from the start. As Paul wrote: “just as He chose us in Him before the foundation of the world, that we should be holy and without blame before Him in love” (Eph. 1:4, NKJV).

 The apostle Paul explains that “just as through one man [Adam] sin entered the world, and death through sin,” so through “the one Man, Jesus Christ,” the gracious gift of eternal life became available to all human beings (Rom. 5:12-21, NKJV). Paul here is making an unambiguous reference to a literal Adam who brought sin and death into this world. One cannot make sense of anything in the Bible without a literal Adam who, through transgression, brought sin and death into our world.

 Thus, the apostle John adds, “God gave us eternal life, and this life is in his Son. Whoever has the Son has life; whoever does not have the Son of God does not have life” (1 John 5:11, 12, NRSV).

 The whole picture becomes clearer in light of Jesus’ statements: “Everyone who looks to the Son and believes in him shall have eternal life, and I will raise them up at the last day” (John 6:40, NIV), and “I am the resurrection and the life. Those who believe in me, even though they die, will live” (John 11:25, NRSV).

 This means that eternal life is a gift of God through Christ, which is secured at the present but fully enjoyed only after the final resurrection of the righteous. The conclusion is very simple: if everlasting life is granted only to those who are in Christ, then those who are not in Him do not have everlasting life (1 John 5:11, 12). By contrast, the theory of the natural immortality of the soul grants everlasting life — whether in paradise or in hell — to all human beings, even to those who are not in Christ. However popular this teaching, it is not biblical.