Okay, that's one verse. And it's more of a confirmation that yes, Christians will have eternal life in the future...and many other scriptures refer to a future time:
Mar 10:29 So Jesus answered and said, "Assuredly, I say to you, there is no one who has left house or brothers or sisters or father or mother or wife or children or lands, for My sake and the gospel's,
Mar 10:30 who shall not receive a hundredfold now in this time—houses and brothers and sisters and mothers and children and lands, with persecutions—and in the age to come, eternal life.
An age to come, the future.
Joh_6:54 Whoever eats My flesh and drinks My blood has eternal life, and I will raise him up at the last day.
Christians are raised up to eternal life at the last day...the future.
Rom 2:5 But in accordance with your hardness and your impenitent heart you are treasuring up for yourself wrath in the day of wrath and revelation of the righteous judgment of God,
Rom 2:6 who "WILL RENDER TO EACH ONE ACCORDING TO HIS DEEDS":
Rom 2:7 eternal life to those who by patient continuance in doing good seek for glory, honor, and immortality;
Here Paul talks about eternal life being granted in the future...when God rewards the faithful and punishes the unjust..
1Ti 6:15 which He will manifest in His own time, He who is the blessed and only Potentate, the King of kings and Lord of lords,
1Ti 6:16 who alone has immortality, dwelling in unapproachable light, whom no man has seen or can see, to whom be honor and everlasting power. Amen. <
Who alone has immortality? Christ.
1Ti 6:17 Command those who are rich in this present age not to be haughty, nor to trust in uncertain riches but in the living God, who gives us richly all things to enjoy.
1Ti 6:18 Let them do good, that they be rich in good works, ready to give, willing to share,
1Ti 6:19 storing up for themselves a good foundation for the time to come, that they may lay hold on eternal life.
Eternal life in a time to come...the future.
Tit 1:1 Paul, a bondservant of God and an apostle of Jesus Christ, according to the faith of God's elect and the acknowledgment of the truth which accords with godliness,
Tit 1:2 in hope of eternal life which God, who cannot lie, promised before time began,
We certainly have the HOPE and promise of eternal life. That's what John is referring to. God will do what he promises...if we overcome.
I have a little explanation on my profile page which might interest you regarding 'to faithe'.If God left it up to me to keep the Grace He Promises in Christ then I would fail because of whom I would be up against. You nor I can ever be worthy of His Grace of God in Christ. Behold, I share with you a mystery ...
Romans 2:17-21
Now you, if you call yourself a Jew; if you rely on the law and boast in God; 18 if you know his will and approve of what is superior because you are instructed by the law; 19 if you are convinced that you are a guide for the blind, a light for those who are in the dark, 20 an instructor of the foolish, a teacher of little children, because you have in the law the embodiment of knowledge and truth— 21 you, then, who teach others, do you not teach yourself?
If you want to ACT like a Jew and boast in the law - good luck - go for it.