Paul states that he who speaks in an unknown tongue edifies himself, but only prophesy (preaching) edifies the Church (1 Corinthians 14:4). Tongue speaking is not something that edifies the Church! He states that if any man speaks in an unknown tongue, that it must be by two or three at the most, and each in turn, one at a time (verse 27). In these Churches today, a lot of people babble and speak in tongues at the same time, and Paul says this should not be. Paul also says that there must be an interpreter (verse 27). But you never hear, in your own language, the interpretation of these tongues in these Churches. That is a direct contradiction of this scripture. Paul says if there is no interpreter, then the tongues must not be spoken in church! 1 Corinthians 14:28, "...let him keep silence in the church; and let him speak to himself, and to God." If a man feels moved to speak in tongues, and there's no interpreter, then he should speak to himself and to God. Therefore, if a man feels moved to pray in tongues, by himself, then that is scripturallybased.
In 1 Corinthians 14, Paul is elevating teaching and preaching over tongue speaking. In fact, Paul says that tongues are not a sign for believers, but for unbelievers (verse 22), while prophesy (preaching) is not for unbelievers, but for believers. So if people want to edify the Church, it is done through prophesy and teaching, and not through tongue speaking, according to scripture.
Bumble Bee - You are right that if done in church scripture says there should be an interpreter, but it says that if there isn't one then it should be done alone. The church that I know about only practise it with a few of them in one of their homes as far as I am aware.
Maddie