Of which I became a minister; did not gradually grow up to the office, but became, at a given time and place, a minister, a διάκονος, a servant. According to the gift of the grace of God. The office of serving Christ was a gift, most undeserved on Paul's part, who had been a persecutor and injurious, but flowing from the free grace of God, his sovereign, unmerited mercy.
Which was given me according to the working of his power. This denotes the manner of the gift; the gift itself, apostleship to the Gentiles, would have been little had it not been accompanied with Divine power.
Spiritual office without spiritual power is miserable; but in Paul's case there was the power as well as the office; not merely the power of working miracles, as some have held, but besides this, the power of spiritual insight into the meaning of Scripture—power of exposition, power of demonstration, power of persuasion.
Paul gratefully acknowledged that all the power of his ministry was God's, not his own (1 Corinthians 3:6, 1 Corinthians 3:7).