If, therefore, the whole church comes together and all speak in tongues, and outsiders or unbelievers enter, will they not say that you are out of your mind? But if all prophesy, an unbeliever or outsider who enters is reproved by all and called to account by all. After the secrets of the unbeliever’s heart are disclosed, that person will bow down before God and worship him, declaring, ‘God is really among you.’ (1Corinthians 14: 23-25)

In considering the "secrets of the unbeliver's heart" I immediatetly think of my sins. I consider those actions and attitudes that separate me from God. I expect prophecy to expose these sins and lead me to contrition, pardon, and reconciliation.

I wonder how much this may suggest an intellectual descent from John Calvin, John Knox, and Jonathon Edwards?

The kruptos kardia - secrets of the heart - may be a unique gift of God, a profound purpose, or a new way of understanding. The secrets made manifest may include the courage to love and serve. What is hidden may be a strength rather than a shame.

Given Paul's emphasis on building-up it is much more likely that prophecy should bring us to recognize our teleios - purpose - rather than focus much on our problems. Some excavation may precede building-up, but the excavation is not the most important element.

If outsiders can find this positive and uplifting secret in our churches, then surely they will find God among us.