Paul declares this in 1 Cor. 15:10 to show his grace-orientation and blessings in God as he was redeemed from being Christ's archenemy of the church who nearly wreaked havoc on its spread. We have no right to look down on the wicked as if we are superior because we were once the enemies of God ourselves! (cf. Romans 5:10). We are to be held to a higher standard and realize that what God holds against sinners is realizing sin and not believing in His Son. But God had mercy on him! George Whitefield said as he saw a condemned man go to the gallows: "There but for the grace of God go I." We must realize that if God withdrew His grace we would be no better than the run-of-the-mill sinner if not worse; we'd be left to our own evil devices or schemes! ("The heart is deceitful above all things, and desperately wicked.. Who can know it?" --Jer. 17:9).
Our righteousness is God's gift to us, not our gift to God! (cf. Isaiah 45:24; Romans 15:18; Hosea 14:8; Isaiah 26:12). This means we all have a dark side that only God knows about; we have seen ourselves for who and what we are and the picture isn't pretty! Christian author Robert Louis Stevenson wrote Dr. Jekyll and Mr. Hyde, we all have an old sin nature that remains after salvation and we must not obey it. We have a new man as well as an old man and the one we feed and nourish the most dominates our demeanor and conduct. We must cease to do evil and learn to do good; it's not automatic or a given. Even the fruit of the Spirit is a given but must be cultivated before it's ripe enough to harvest. We will reap what we sow.
The wicked live by the rule of the jungle, each man for himself, looking out for Number One while trying to win the rat race. But his reward is in this life (cf. Psalm 31:15) and we are not to get too comfortable in our temporary abode as we are citizens of heaven and only passing through on a green card and are in a dry run or staging area, or dress rehearsal for our permanent home with the Lord. We have salvation in three tenses: our past is forgiven, our present is given meaning, and our future is secured. We are saved from the penalty of sin, we are being saved from its power, and we shall be saved from its presence.
Our lives stand in contrast to the wicked who lives for the here and now and virtually eats, drinks, and is merry as if he were ot die tomorrow. The wicked do what is right in their own eyes and live for themselves, not some higher purpose or power. Essentially, they waste their lives and have no ultimate purpose, meaning, dignity, or worth. They live according to what is right in their own eyes go their own way, or act according to feelings or worse yet, libido. (cf Judges 17:6; 21:25; Isaiah 55:6). When you don't surrender to the Lordship of Christ, you surrender to Satan's chaos and evil. There's no middle ground of neutrality!s The central question of humankind is: What think ye of Christ? Even Christians can be deceived by the devil and held captive by him to do his will (cf. 2 Tim. 2:26) and should pray to be delivered from the evil one as the Lord's prayer says.
We should realize that the wicked are self-condemned by their own conscience (cf. Romans 2:14-15) and will all be judged by our works either for reward as Christians or for salvation for the lost (cf. Romans 2:6; 2 Cor. 5:21; Matt. 16:27; Psalm 2:12). God's kindness and goodness are meant to lead them to repentance (cf. Romans 2:4). We are held to a higher standard and should realize that God can convert the wicked just like He converted us! No one who repents is too far gone for grace! (cf. Isaiah 1:18). But the wicked are too proud to seek God and believe they are not accountable since they reckon Him as dead and do not see their own sin due to their pride. (cf Psalm 10:4); none seeks God! (cf Psalm 14:2). Soli Deo Gloria!