I Corinthians 15:8-10
And last of all He appeared to me, also, as to one abnormally born.
Paul considered himself to be an "abortion," born out of the proper time for him to live; either coming to faith too late, after the right time to be an apostle; or born too soon, before the "end days" he wrote about. He considered that he lived at the "wrong" time period, not realizing his own importance in planting the Church all over the known world at that time.
For I am the least of the apostles and do not deserve to be called an apostle, because I persecuted the Church of God.
Paul is beating himself up here, for what God had already forgiven him for, when He called him to faith in Christ.
But by the grace of God I am what I am, and His grace to me was not without effect.
Here Paul admits that it is only by God's undeserved favor that he is the man he is "today," not the old man he used to be in the flesh.
No, I worked harder than all of them--yet not I , but the grace of God that was with me.
The effect of God's grace on Paul's life was that he worked so hard, constantly, to repair the damage he had done, turning around 180 degrees from the man he had been before. This is proof of God's working in him.
Whenever God gets hold of someone, there is a definite change in that person's thought processes, leading to a changed life-style, in turning away from the worldly way we used to live, turning toward God and His ways.
How has your life changed since God saved you?
Even so, come, Lord Jesus!
