First things first. When do you think Paul received his revelation? And what specifically is this revelation?
Paul doesn't say when, he just tell us he had a revelation, Gal. 1:15-16
15 But when it pleased God, who separated me from my mother's womb, and called me by his grace,
16 To reveal his Son in me, that I might preach him among the heathen; immediately I conferred not with flesh and blood:
The revelation is of the Indwelling Christ revealed as the only life of the believer, Gal. 2:20
20 I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.
We have no life of our own, the only life we have as believers is the Christ life.
It's like the new creation, that is not you without Christ, and it's not Christ without you, the two have become one, that makes the new creation.
Al of this comes about by a birthing, we have been born again, birthed by God the Father.
He takes the incorruptible seed, Christ, and places Him in you the moment you believe.
We learn Christ now, thats what makes a Christian, the believer learns to express the life that is in him, Christ.
He needs your mind, the uniqueness of your creation to flow out of you with all His character and personality, known as the fruit of the Spirit.
That takes time to learn, study Paul said to show yourself approved, it takes revelation, the same revelation Paul had. Its there for the believer, it's not hidden, it is nolonger a mystery.
We have the greatest teacher there is, the HolySpirit, He makes this truth known to any believer that so hungers for the things of God.