The promise of eternal life, or everlasting life, is the great promise given to us in the message of salvation through Jesus Christ. Much of the Scriptural basis for eternal life in Christ is found in the writings of the Apostle John, in his gospel, and in the epistles he later wrote to the early Church.
John 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
These are the words of Jesus, in His discourse with Nicodemus, the Pharisee who came to Him by night. Jesus talked with Nicodemus about how a man must be born from above to even perceive the kingdom of God, and that this new birth was a birth of the spirit of the man, not of his flesh. Jesus explained to Nicodemus how that the Son of man must be lifted up, the same way that Moses had lifted up the serpent in the wilderness. This, of course, was a reference to the crucifixion that Jesus would later endure.
John 3:14-15 And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up: That whosoever believeth in him should not perish, but have eternal life.
Why was Jesus to be lifted up in crucifixion? So, according to this verse, that men could believe on Him. It is in believing in Jesus, and in the work of Calvary’s cross, that eternal life is procured for us, so that “whosoever believeth in him should not perish, but have everlasting life.”
It was the divine purpose of God, in sending His Son , that men would not perish, but rather believe on His Son and have eternal life.
John 3:36 He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him.
These words are from the mouth of John the Baptist, as he endeavored to explain who he was, in the divine scheme of things, that he himself was not the Christ, pointing rather to Jesus, saying that he who believes on the Son of God has eternal life. And he who does not believe is already living under the wrath of God, and will not even see life, much less experience it.
It is evident in this verse (John 3:36) that the word “life” is not merely referring to the life of the physical body, as opposed to physical death. John the Baptist states that the one who doesn’t believe on Jesus will not even see life, even though that person is physically alive. So then, it is possible to be alive, but not have the life that he is talking about.
He also states that the one who does not have this life, the life that comes from believing on God’s Son, is abiding under the wrath of God. It is true that there may be wrath to come, but this verse tells us that God’s wrath is already in the earth, and in full operation. But in Christ we escape that wrath, and live in God's peace.
So then, what is the life he is talking about? Fortunately, the Bible tells us plainly what eternal life is. It defines eternal life, or everlasting life, as fellowship with God, the Father, and with His Son, Jesus, as seen in the following Scriptures.
John 17:3 And this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent.
1 John 1:2-3 (For the life was manifested, and we have seen it, and bear witness, and shew unto you that eternal life, which was with the Father, and was manifested unto us;) that which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship is with the Father, and with his Son Jesus Christ.
Eternal life is knowing God, and having fellowship with Him. And through that fellowship we are partakers of His life, His eternal life, the life of God, by knowing and fellowshipping with the Father and with the Son.
By the same token, death is separation from God, or, that is, broken fellowship with Him. Adam was told that in the day that he ate of the forbidden fruit, he would die. Yet, after he ate the fruit, he lived physically for many more years. But he did actually die on that day. He died spiritually, as his fellowship the God, the source of Adam’s life, was broken.
Biblically speaking, that is what death really is. Physical death is an extension of spiritual death. This death that Adam experienced, this separation from God, was passed down to all men who came after him, and death reigned over mankind. The ability to escape that condition of spiritual death came with Jesus Christ, Who came that we might have life, and have it in abundance.
John 10:10 The thief cometh not, but for to steal, and to kill, and to destroy: I am come that they might have life, and that they might have it more abundantly.
John 11:25-26 Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live: And whosoever liveth and believeth in me shall never die. Believest thou this?
Jesus declared to Martha the He, Jesus, was and is the resurrection. And when He raised Lazarus from the dead, He manifested Himself as the resurrection. On the day of resurrection, eternal life will bring forth those who are in Christ, even though they have experienced the death of the physical body.
Eternal life is a spiritual life imparted to the human spirit when an individual is born from above, born of the spirit. Eternal life is yet to come, but as believers in Jesus Christ, we have eternal life now, even in this present age, and in this present life.
John 5:24 Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.
The word translated here as “condemnation” means judgment of damnation. Jesus says in this verse that the one who has everlasting life, or eternal life, does not come into damnation or judgment. So, eternal life is clearly an escape from judgment that one would otherwise experience.
That person is passed from death unto life. Does that happen when they die physically? No. It happens when they hear His word, and believe on the One Who sent Jesus. That’s when they are passed from death unto life, when they believe on Jesus, when they become a believer.
1 John 5:11-12 And this is the record, that God hath given to us eternal life, and this life is in his Son. He that hath the Son hath life; and he that hath not the Son of God hath not life.
This is the conclusion. God has given us eternal life, and that eternal life is in the form of His Son coming to earth to pay the price for our sins. If we believe on Him, and receive Him through faith, we have, that is, we already have, eternal life. However, without believing and receiving His Son, we simply do not have the eternal life that God sent through Jesus, but are abiding under God's wrath.