13. Therefore, the person who speaks in an [unknown] tongue should pray [for the power] to interpret and explain what he says.
14. For if I pray in an [unknown] tongue, my spirit [by the Holy Spirit within me] prays, but my mind is unproductive [it bears no fruit and helps nobody].
15. Then what am I to do? I will pray with my spirit [by the Holy Spirit that is within me], but I will also pray [intelligently] with my mind and understanding; I will sing with my spirit [by the Holy Spirit that is within me], but I will sing [intelligently] with my mind and understanding also.
16. Otherwise, if you bless and render thanks with [your] spirit [thoroughly aroused by the Holy Spirit], how can anyone in the position of an outsider or he who is not gifted with [interpreting of unknown] tongues, say the Amen to your thanksgiving, since he does not know what you are saying? [I Chron. 16:36; Ps. 106:48.]