Singing in tongues according to St. Augustine

Saint Augustine gives a very fitting description of it :

“This is how he gives you a way of singing. Do not seek for words, as though you could explain what God delights in. Sing in jubilation. For this is singing well to God, singing in jubilation. What is singing in jubilation ? Understanding but being unable to explain in words, what is sung in the heart … for the ineffable is he of whom you cannot speak. And if you cannot speak of him, and ought not to keep silent, what remains but that you utter a shout for joy. That the heart should rejoice without words, and that the limitless expanse of joy should not bear the constraint of syllables.” (Commentary on Psalm 32).