Is there anything more annoying than jesus retards offering thoughts and prayers

I am struggling to understand 1 Corinthians 6, Paul basically says (to the Corinthians) you were once sinners, and have been saved by Jesus, but even after you were saved, you continued to sin, and are therefore betraying God. If I'm reading this right I just see a negation of Jesus' sacrifice, I think the Corinthians were correct to believe they are saved from sin once and for all, and that Jesus' death and resurrection wasn't just a temporal cleansing of prior sins. Paul seems to imply you need to live a perfect life after you have been cleansed of sin in order to actually go to heaven, which means Jesus' sacrifice was effectively meaningless. Jews already had ways to cleanse themselves of sin before Jesus. How could Jesus be important if he does not forgive all sins forever unconditionally? Literally what would the point be otherwise? The entire concept of sin in Christianity seems contradictory to the supposed importance of Jesus and the salvation he offers, if it is at all possible to go to Hell as a faithful Christian, regardless of whatever sins you commit, then Jesus died for nothing, his gift of salvation has conditions and is therefore no different to the pre-Christian era where regular ritual cleansing was necessary.