Speaking in tongues is one of the ways the Holy Spirit manifests Himself. The church speaks a different language than the rest of the world. In doing so, we represent the culture of heaven and invite the world to repentance.
The central mystery in Christianity is the Trinity. It’s intentionally a paradox because we aren’t meant to understand it. Rather, we’re meant to humble ourselves and enjoy the beauty and wonder the proceeds from mystery. As we embrace the mystery of things like God and love, the smaller riddles of life are untangled.