“One born out of due time.”-1 Corinthians 15:8

It was necessary that Paul, as an apostle, should have seen the Lord. He was not converted at the time of Christ’s ascension; yet he was made an apostle, for the Lord Jesus appeared to him in the way, as he was going to Damascus to persecute the saints of God. When he looked upon himself as thus put in, as it were, at the end of the apostles, he spoke of himself in the most depreciating terms, calling himself, “one born out of due time.” Those who are acquainted with the Greek tongue know what a despicable term Paul here applied to himself,-as though he was scarcely a man at all,-at any rate, as the very last of the family, “born out of due time;” and not only the last, but also the very least, for he says, “I am the least of the apostles, that am not meet to be called an apostle, because I persecuted the church of God.” 

Paul proved that he was a true citizen of the New Jerusalem because he became, of all men, most zealous for Christ, zealous for the gospel, zealous for the winning of souls; he seemed to try to do all he could to undo the mischief he had wrought in the days of his unregeneracy, and to work with both his hands and all his heart to establish and extend the kingdom which once he tried to overthrow. O God, by Thy great mercy, cause another Paul to be born in this house of prayer! Thou canst do it; wilt Thou not bring to Thyself, by the power of the Eternal Spirit, some wild, threatening, blustering, blaspheming hater of Christ, lay him at the dear feet of the Crucified, and cause him to look up and live? Pray for this, dear Christian people. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2663.cfm