There is always a purpose

God says:

Whenever you pray in tongues there is always a purpose.
It is never just nonsense, just foolishness. The foolishness is Mine alone!
Do you really think you could express spiritual things in the pedantic form of words or natural images—it’s too slow—too one dimensional—too limited. Tongues can say many things at once in a spiritual way. Tongues, sighs, groans, shouts (yes, ho’s!) and movements in the Spirit communicate many things to many beings—sometimes the whole spiritual realm at once.
There is overlap between spiritual and earthly/mortal communication (St Paul “I will pray with the Spirit and with the mind”) and it is always possible to have some idea with your mind of what is happening in tongues. It is not always a good idea to know but it’s always a good idea to ask Me if it’s suitable, relevant or useful to know.

Remember I am bigger than any principality or power but certainly your tongues might be addressing a principality or power or a very, very tiny matter. It might be providing a shield around you or a spiritual cocoon in which you take on a new spiritual form, identity or purpose. No—you might not have to be in it for weeks like a larva—it might be quick! Your tongue might be watering or refreshing your own soul or someone else’s. It might be sending some spiritual data to some one or groups of people or receiving some for yourself, like spiritual download to the hard-drive.

Did you really think tongues would be just to present a sign to someone that they had received baptism in My Spirit? Of course ‘tongues’ is a heavenly language, the language of angels and the way into heavenly realms.

Do you know, my will brings such happiness.
This is my desire—my great love is to bring happiness. I want to bring you happiness as we grow in closeness.
So tongues can bring into effect actions, transmissions and ministries of my heavenly beings -for example, although angels and spiritual beings will flock to fervent prayer on earth by nature they are also called by tongues and called into action by tongues. These ministering spirits are very powerful and diligent in working on your behalf – to bless and heal and sort out and prosper and make good.