Many don’t understand that the gift of tongues and our prayer language are really two different things. Same tongue, but two different uses. We are told in I Cor. 14:13: “Therefore let him who speaks in a tongue pray that he may interpret.” This is “speaking” in tongues in the church, and is the gift mentioned in 1 Cor. 12.
On the other hand, there is praying and singing in tongues, which is mentioned in 1 Cor. 14:14-15, “For if I pray in a tongue, my spirit prays, but my understanding is unfruitful (meaning I don’t understand what I am saying). What is the conclusion then? I will pray with the spirit, and I will also pray with the understanding. I will sing with the spirit, and I will also sing with the understanding.”
It is the latter that we call our prayer language which I believe we should be using at all times, praying continually, which leads to spirit-led prayer with our understanding. That needs no interpretation. This is what Jude is talking about in vs. 20, “But you, beloved, building yourselves up on your most holy faith, praying in the Holy Spirit.” (Written and first posted January 28, 2013).