This is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent. (John 17:3)
And this is the testimony: God has given 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)
The thing that makes eternal life eternal is God Himself. It is His life — it comes from Him and He shares it with us. It is the life of Christ in us. It is the Spirit of God in us, continually ministering life to us. It is, to use the words of 2 Peter 1:4, being “partakers of the divine nature.” Eternal life has everything to do with God.
The quantitative aspect of this life — that it is eternal — is a result of the qualitative aspect — that it is divine. The primary aspect of this life and this salvation, out of which all other aspects flow, is being reconciled with God. In His prayer in the garden of Gethsemane on the night before He was crucified, Jesus said, “This is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent” (John 17:3).
Eternal life is all about knowing God through Jesus Christ. This is not merely knowing about God, but knowing God Himself. And not just knowing about Christ, but knowing Christ Himself. It is an ongoing personal relationship with God, being reconciled to Him through Christ. The Greek verb for “know” in John 17:3 is in the present tense and indicates continuous action.
Knowing God through Christ is not merely a means to an end. It is the purpose as well as the source of eternal life. Indeed, knowing God is the essence of eternal life, and it is found in Jesus Christ.
For it pleased the Father that in Him [Christ] all the fullness should dwell, and by Him to reconcile all things to Himself, by Him, whether things on earth or things in heaven, having made peace through the blood of His cross. (Colossians 1:19-20)To enter into salvation, then, is to enter into that reconciled relationship with God. We enter it through Jesus Christ. “Whoever has the Son has life,” says John. A person who does not want that relationship does not really what salvation but something that does not exist. The salvation Jesus offers is life, eternal and divine, given freely and received by faith. And this gift of life is ... Himself.