'Intelligently' in the Bible

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].

nevertheless, in public worship I would rather say five understandable words in order to instruct others, than ten thousand words in a tongue [which others cannot understand].