What does 1 Corinthians 12:27 mean?

Now Paul makes his illustration—human body as the body of Christ—very personal for the church in Corinth. He speaks to them directly and with purpose. They are both the body of Christ together as a group, and they are individual members of the body of Christ.

In prior verses, Paul has noted that the diverse members of the body must work together, according to their designed roles, in order for the body to function. This is not only good for the body, it's good for each individual member.

Everything Paul has written in the chapter applies to the Corinthian believers and their experience of spiritual gifts. This means if they are willing to set aside their discontent about the role God has given to them in the church, and their arrogance about not needing other members of the body of Christ, they have the opportunity to thrive together to become what God intends for the church to be.

The same application is meant to be taken on by all believers, in all churches, even today.