“But when it pleased God, who separated me from my mother's womb, and called me by his grace,”
King James Version (KJV)
1:15 But when it pleased God - He ascribes nothing to his own merits, endeavours, or sincerity. Who separated me from my mother's womb - Set me apart for an apostle, as he did Jeremiah for a prophet. #Jer 1:5|. Such an unconditional predestination as this may consist, both with God's justice and mercy. And called me by his grace - By his free and almighty love, to be both a Christian and an apostle.
Ga 1:15 But when it pleased God, etc. The language that follows implies that, like Moses, John the Baptist (Lu 1:15-17), Isaiah (Isa 49:1), and Jeremiah (Jer 1:5), Paul was destined to his work from birth.