I Corinthians 14
The gospel of Jesus - the whole complete story of His perfect life, substiutionary death, burial, resurrection, and reign - must be what the Church is talking about and it must make sense.
This is what the Bible says in I Corinthians 14. This is the main idea - in a chapter that might otherwise be seen only as instruciton for how some of the miraculous spiritual gifts function in the church. But under-girding all of the talk of what it means for people to be spiritual is this: the story of Jesus is of first importance, therefore it must be not only what our lives are built on but also everything that we're talking about, and - when we talk about it - it must make sense.