“For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.”
King James Version (KJV)
14:14 If I pray in an unknown tongue - The apostle, as he did at #1Cor 14:6|, transfers it to himself. My spirit prayeth - By the power of the Spirit I understand the words myself. But my understanding is unfruitful - The knowledge I have is no benefit to others.
1Co 14:14 If I pray in an [unknown] tongue, etc. He does not understand, and only his spirit prayeth.