This is a vigorous take on Psalm 99 (100) by Lucien Deiss. I looked at it in AOV about fifteen years ago.
It is an old WLP copyright and you can still buy the sheet music at GIA for $0.80. John de Luca notes that he slightly adapted the antiphon to better suit SATB, but I can’t see major changes except the excellent idea of dropping the key from Bb to Ab.
The text is here.
My backing is more fake BIAB church organ.