I had grown up a Presbyterian Christian who believed that as long as you were a Christian who believed in Jesus, you belonged to the 'church.' It didn't matter which church you belonged to or where you went to worship on Sundays, it just mattered if you believed in Jesus. If you believed in Jesus, you were doing just fine.
St. Paul had to deal with a lot of 'high minded', philosophical types in his day. Most were very prideful, long on academics but short on humility. Some people back then claimed that Jesus didn't really rise from the dead (as we celebrate this weekend). Rather than mince words, Paul gave it to them straight (in the verse up above). Many people will tell you that 'based on human logic' the Resurrection makes no sense. The first thing we need to remember is that 'human logic' is not omnipotence. God makes it very clear that '(His) ways are not our ways, nor are His thoughts our thoughts.' (Is. 55:8-9)