1 Corinthians 14:13-15

Therefore let one who speaks in a tongue pray that he may [be gifted to] translate or explain [what he says]. For if I pray in a tongue, my spirit prays, but my mind is unproductive [because it does not understand what my spirit is praying]. Then what am I to do? I will pray with the spirit [by the Holy Spirit that is within me] and I will pray with the mind [using words I understand]; I will sing with the spirit [by the Holy Spirit that is within me] and I will sing with the mind [using words I understand].