1 Cor. 14:20-25 (ESV)
Brothers, do not be children in your thinking. Be infants in evil, but in your thinking be mature.  In the Law it is written, "By people of strange tongues and by the lips of foreigners will I speak to this people, and even then they will not listen to me, says the Lord."  Thus tongues are a sign not for believers but for unbelievers, while prophecy is a sign not for unbelievers but for believers.  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 minds?  But if all prophesy, and an unbeliever or outsider enters, he is convicted by all, he is called to account by all,  the secrets of his heart are disclosed, and so, falling on his face, he will worship God and declare that God is really among you.
There is an aversion to day in Christian circles to thinking. Theology, and philosophy are often maligned as being of the devil. No doubt some theologies and philosophies are. “Just believe!” is the chant. An unwarranted and unhelpful wedge is driven between reason, and faith. We don’t believe in the irrational. Paul here speaks against this just believe mentality. Be mature in your thinking, he tells us. Thinking is a good thing. Think about what you believe, and how you present it. We can’t expect people to abandon reason, we ourselves do not. But we do make spectacles of ourselves, when we are uncritical in the presentation of our belief.
Paul then begins to talk about this presentation first and foremost in worship. He takes the Corinthians to task for their un-orderly use of tongues in worship. These do not build up, they do not convict. We ought to think carefully about how we worship, and why. Worship is for all, children, parents, grandparents, believers and the unbelievers who enter. It should be done tactfully so that all are edified. It should not be done in a selfish manner that only appeals to a certain segment, or demographic of our population. Such as services aimed at young adults, to the exclusion of grand parents, or those who are younger. We need to be critical of the music we use, the sermons we preach, the confessions we make. We should not do it in away that only appeals to outsiders, or seekers. It would be much better to teach the seekers what we are doing and why. This will require us to be mature in our thinking.