Many use the example of the Corinthians to say that carnal, lawless people can still be saved. As a result, often when someone who claims salvation in Christ lives in sin someone will bring false comfort to the situation, acting like it's not such a big deal, saying nonchalantly "even the Church in Corinth had the same problem." However, Paul made it a HUGE DEAL in his letter to the Corinthians and gave them very stern warnings that those in sin could not be saved in the end if they continued on their present course and did not live according to the life of Christ in them.
"Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God. And such were some of you: but ye are washed, but ye are sanctified, but ye are justified in the name of the Lord Jesus, and by the Spirit of our God." (1 Corinthians 6:9-11)
Paul said not to be deceived into thinking that any unrighteous (lawless) person would inherit the kingdom of God. Some say that "Such were some of you" in the last sentence (vs.11) means that God did not count the sinning Corinthians as unrighteous anymore, even though they were living that way. If that is so, then why did Paul give the warning that such lawless people wouldn't inherit God's kingdom if that didn't apply to his audience, whose very sins Paul was dealing with? Why the warning not to be deceived that such wouldn't inherit the kingdom of God if the warning didn't apply to the very recipients of the letter? It's obvious that that those in sin do need to repent and bring forth fruit meet for repentance whether they were ever truly converted at one point or not (Matthew 3:10, Luke 3:9). If any dispute this further though, Paul would go on to make it clear to the Corinthians that they needed to judge themselves and repent or else be condemned with the ungodly world.
"For if we would judge ourselves, we should not be judged. But when we are judged, we are chastened of the Lord, that we should not be condemned with the world." (1 Corinthians 11:31-32)
Consider with this the necessity the New Testament gives of responding to chastening from God. "For whom the Lord loveth he chasteneth, and scourgeth every son whom he receiveth. If ye endure chastening, God dealeth with you as with sons; for what son is he whom the father chasteneth not? But if ye be without chastisement (present tense- referring to not enduring chastening, the enduring spoken of in the previous sentence), whereof all are partakers, then are ye bastards, and not sons." (Hebrews 12:6-8)
We are then told that enduring chastening means being subject to God. And we are told then what the result of enduring chastening is. "Furthermore we have had fathers of our flesh which corrected us, and we gave them reverence: shall we not much rather be in subjection unto the Father of spirits, and live? For they verily for a few days chastened us after their own pleasure; but he for our profit, that we might be partakers of his holiness. Now no chastening for the present seemeth to be joyous, but grievous: nevertheless afterward it yieldeth the peaceable fruit of righteousness unto them which are exercised thereby." (Hebrews 12:9-11)
Paul took it very seriously that the Corinthians not continue in sin. Thus we see in his writing of 2 Corinthians the insistence that any still in sin repent immediately. "For I fear, lest, when I come, I shall not find you such as I would, and that I shall be found unto you such as ye would not: lest there be debates, envyings, wraths, strifes, backbitings, whisperings, swellings, tumults: And lest, when I come again, my God will humble me among you, and that I shall bewail many which have sinned already, and have not repented of the uncleanness and fornication and lasciviousness which they have committed." (2 Corinthians 12:20-21)
Sadly, many are quick to notice the verses about the Corinthians in sin. Yet few seem to notice the sober instruction and the dreadful warnings given to those very same Corinthians in sin.