οτε δε ευδοκησεν ο θεος ο αφορισας με εκ κοιλιας μητρος μου και καλεσας δια της χαριτος αυτου
αποκαλυψαι τον υιον αυτου εν εμοι ινα ευαγγελιζωμαι αυτον εν τοις εθνεσιν ευθεως ου προσανεθεμην σαρκι και αιματι
Galatians 1:15 and 16, TR (undisputed)
But when it pleased God, who separated me from my mother's womb, and called me by his grace,
To reveal his Son in me, that I might preach him among the heathen; immediately I conferred not with flesh and blood:
Galatians 1:15 and 16, KJV
As Paul develops his argument towards the Galatian churches he states his own calling and his own experience.
What is the meaning of 'reveal' - αποκαλυψαι - his Son ?
What does he mean by the revelation being 'in' - εν εμοι - himself ?
This cannot refer, only, to a taught knowledge from an exterior source. If the knowledge of Christ were only a knowledge that is accumulated through reading, or through human teaching, then there were no need of 'revelation' by God. And no need of an 'inward' revelation.
What did Paul experience ? What is he conveying by this expression ?
Clearly, from his words, he is informing us what occurred to him. So this is not a matter of opinion, not a matter of speculation that we must guess at what he experienced. His words are intended to inform us about what was his inward reception of divine influence.