Listen to what Paul says about it in 1 Corinthians 14:2-4: “For one who speaks in a tongue [an unknown tongue] does not speak to men, but to God; for no one understands, but in his spirit he speaks mysteries. One who speaks in a tongue edifies himself...” So, what are we doing when we pray in this prayer language, this unknown tongue?
Paul says we’re doing three things. First of all, we’re speaking direct to God, not to man; that’s a privilege in itself, to be able to speak directly to Almighty God. Secondly he says, in our spirits we’re speaking mysteries, things too deep and profound for our little minds fully to grasp. Thirdly he says, when we speak in a tongue we’re edifying or building ourselves up spiritually even though our mind doesn’t really understand all that’s going on…
My name is Cesar from a Voice in the Desert