There are “new tongues” (Mark 16:17); i.e., languages that are new to the speaker which he has never learned before. There are “other tongues” (Acts 2:4; 1 Cor. 14:21); those are languages not native to the speaker, which he may (1 Cor. 14:18) or may not (Acts 2:4) have learned, but which are understood by the hearers (Acts 2:8). Here in 1 Corinthians 14, Paul speaks of “unknown tongues.” These are languages that are unknown to everyone in the congregation and, therefore, need an interpreter, whether it be the speaker (vs. 13) or someone else (vs. 27). The Corinthians were talking in languages which nobody in the congregation knew. If someone is doing that then they “speaketh not unto men, but unto God.” The only one who understands the language is God. And have no doubt about it, what Paul is talking about here is a language (13:1), Now, if you are speaking in an unknown language, then you are speaking “mysteries” (vs. 2). These are not mysteries as in 1 Corinthians 4:1; these are mysteries insomuch as no one understands what you are saying. Look at verse 16, “Else when thou shalt bless with the spirit, how shall he that occupieth the room of the unlearned say Amen at thy giving of thanks, seeing he UNDERSTANDETH not what thou sayest?” Notice the second thing about this. “Howbeit in the spirit he speaketh mysteries.” In the what? Well, that isn’t the Holy Spirit.