1 Corinthians 14:16

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.]