The elect or chosen were given Eternal Life in Christ before the world began, for it was one of the Many Spiritual blessings they were blessed with ..
Eph 1:3-4
3Blessed be the God and Father of our Lord Jesus Christ,
who hath blessed us with all spiritual blessings in heavenly places in Christ:
4According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love:
This is what John meant here
1 Jn 5:11-12
11And this is the record, that God hath given to us eternal life, and this life is in his Son.
12He that hath the Son hath life; and he that hath not the Son of God hath not life.
Notice, God hath given [ not offered, not made available] us eternal life, and this life is in His Son [ Christ]..
Now, pay close attention, When we are born into this world, it is according to Gods [ not mans freewill] set time [season] and purpose..
Ecclesiastes 3:1-2
1To every thing there
is a season, and a time to every purpose under the heaven:
2A time to be born, and a time to die;
And it is evidenced that we had a being or union with Adam in the beginning, which meant, that in Him [ Adam] God
had given us physical, earthly life .. Being born into the world [ at Gods time and season for us] did not make us the Natural Sons and Daughters of Adam, that occurred in our original creation in him as his seed or posterity, for it was that which constituted the relationship, and consequently, our being born physically and made manifest.
Basically since we had already been given physical life in Adam, it was only a matter of time that the physical life would be made manifest and become active..
Now the same thing is True by those who have eternal life, who are believing on Jesus Christ, for believing on Him is indicative of having been given eternal life in Him..
Jn 5:24
24Verily, 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.
Jesus is saying here, He that is hearing my word and believing Gods testimony from Him, has everlasting life..for the implication is, having eternal life dwelling in them at that time, is why they were Hearing Jesus voice or word and believing His testimony that it was From God...
And John writes in His epistle this
1 Jn 5:1
1Whosoever believeth that Jesus is the Christ is born of God:
Again this is saying, believing that Jesus is the Christ, is evidence of having already been born of God..
Believeth here is present tense [now believing ] but
is born of God is perfect tense.. Strong's greek describes the perfect tense:
"The perfect tense in Greek corresponds to the perfect tense in English, and describes an action which is viewed as having been completed in the past, once and for all, not needing to be repeated."
Being born of God was something that happened in the past prior to the believing in the present..so the believing is logically the effect or evidence of the having been born of God...and being born of God and experimentally having eternal life are the same.. The New Birth is the communication of Eternal life to those it was given to in the Son before the foundation of the world..
John teaches this to in His gospel
John 1 :12-13
12But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:
13Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.
Those, the
as many as received Him, even them that believed on His Name..
vs 13 Had been born of God, thats what caused the effects of vs 12..
And being born of God means one had eternal life communicated to them from above by the Holy Ghost...