1 CORINTIAMS 14:2 For the one who speaks in a tongue does not speak to people, but to God; for no one understands, but in his spirit he speaks mysteries.
THE POWER OF SPEAKING IN TONGUES

I truly believe speaking in tongues is the ultimate weapon for spiritual battles we as believers face on a daily basis.
Isaiah 28:11 KJV
For with stammering lips and another tongue will he speak to this people.
1 Corinthians 14:2 NASBS
For one who speaks in a tongue does not speak to men but to God; for no one understands, but in his spirit he speaks mysteries.
Romans 8:26-27 NASBS
In the same way the Spirit also helps our weakness; for we do not know how to pray as we should, but the Spirit Himself intercedes for us with groanings too deep for words; and He who searches the hearts knows what the mind of the Spirit is, because He intercedes for the saints according to the will of God.
John 3:5 YLT
Jesus answered, `Verily, verily, I say to thee, If any one may not be born of water, and the Spirit, he is not able to enter into the reign of God;