[renee819]

Justin, I go into this more thoroughly in the Debate Room under Salvation Issues. “The difference in Other Tongues and Unknown Tongues.

The main difference is---Other Tongues is a foreign language. And anyone close by the speaker that understands that language, can interpret it.
The purpose? As evidence when a person receives the Holy Ghost. And we are never told of any other evidence of the Holy Ghost, in the Bible.

Unknown Tongues---no man understands, unless God gives the interpretation. I believe that Unknown Tongues is God's language.

The purpose,...

It is our prayer language, in private prayer at home. (It is easier to pray in Unknown tongues than it is to pray in English, or whatever a persons native language is.)

It edify's the speaker. Builds up their spirit.

We are praying directly to God, and we are speaking mysteries. (It has been my experience, when I spend a lot of time in unknown tongues (Privately) I can write better. Think better. Keep my mind more on spiritual things easier.)

When it is spoken at church, it should be one at a time and wait for the interpretation, and then, it becomes Prophecy.

Whereas with Other Tongues (people receiving the Holy Ghost) can be by the hundreds if God so chose. Like the 120 at Pentecost.