Was speaking in tongues done in the Old Testament? The reason I ask is because talking in tongues is nothing more speaking in a language not known to the user. I know it won't be a critical or applicable statement, but didn't even a donkey speak in tongues with Balaam? I know it says God opened the donkey's mouth and all, but would that be speaking in tongues? That even a donkey spoke in tongues which is kind of funny. I won't use it as a essential point, but I talking a year ago to a friend who says he speaks in tongues. I told my friend if you want to get into it, even a donkey spoke in another language. At the time he and I were discussing if sinful people can prophecy and can the Spirit come upon people to make them do things. (The answer was yes with Saul and his guys he sent after David plus Balaam and all. It shows that the Spirit can do what He wants.) My friend and I like to give each other a hard time with subjects we disagree about so I threw that out there as a joke, but I realized it might actually be considered talking in tongues.
I had never considered it in that light, but yes, the donkey was speaking in a language which it did not know prior and wasn't trained in. But there is much more going on since that particular miracle had to have raised the donkey's intelligence quite a bit so it could reason with Balaam and there would have been modifications to it's voice box to accommodate human speech.
The first mention of speaking in tongues as a miraculous gift to humans is in Acts 2. Since it was unknown prior, Luke included a definition of what speaking in tongues meant. "And when this sound occurred, the multitude came together, and were confused, because everyone heard them speak in his own language. Then they were all amazed and marveled, saying to one another, "Look, are not all these who speak Galileans? And how is it that we hear, each in our own language in which we were born?"" (Acts 2:6-8). Being able to speak Russian to a Spaniard would not be impressive. In Acts 2 there there 15 different regions of the world mentioned. Each with its own native language, and the apostles were able to converse with them in their own tongue.
The origin of languages, or tongues, is mentioned in Genesis 11:1-9. But the ability to speak to people in a language which you never studied is only mentioned in the New Testament.