1Co 14:1 Follow after charity, and desire spiritual gifts, but rather that ye may prophesy.
1Co 14:2 For he that speaketh in an unknown tongue speaketh not unto men, but unto God: for no man understandeth him; howbeit in the spirit he speaketh mysteries.
1Co 14:3 But he that prophesieth speaketh unto men to edification, and exhortation, and comfort.
1Co 14:4 He that speaketh in an unknown tongue edifieth himself; but he that prophesieth edifieth the church.
1Co 14:13 Wherefore let him that speaketh in an unknown tongue pray that he may interpret.
1Co 14:14 For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.
1Co 14:15 What is it then? I will pray with the spirit, and I will pray with the understanding also: I will sing with the spirit, and I will sing with the understanding also.
1Co 14:16 Else when thou shalt bless with the spirit, how shall he that occupieth the room of the unlearned say Amen at thy giving of thanks, seeing he understandeth not what thou sayest?
1Co 14:23 If therefore the whole church be come together into one place, and all speak with tongues, and there come in those that are unlearned, or unbelievers, will they not say that ye are mad?
1Co 14:24 But if all prophesy, and there come in one that believeth not, or one unlearned, he is convinced of all, he is judged of all:
1Co 14:39 Wherefore, brethren, covet to prophesy, and forbid not to speak with tongues.
1Co 14:40 Let all things be done decently and in order.
Tongues or languages spoken in the church should be understood by the hearer, either in his own language or if in an unknown tongue, they must be interpreted so as to edify the hearers. Speaking in an unknown tongue, words or sounds in private to the LORD edifies the speaker. The Holy Spirit speaks for you. Speaking in tongues in some full gospel churches is a sign of the Holy Spirit. Some churches forbid to speak in tongues. All things are to be in order. An unknown tongue is to be interpreted by the speaker or by someone in the church. We are to edify the church with words from the Lord that are understood. A number of tongue speakers speaking at once is confusion and a new person in the church would probably not return, it is confusion to him. Speak words to edify, not to just edify yourself. Some people are easily offended so be sensitive in the spirit and do all things in love.