While there are plenty of conflicting opinions about which Christmas songs are the best—Wham!’s “Last Christmas,” for example—and which are the worst (Looking at you, “Dominick the Donkey”), the oldest Christmas carol is probably missing from every heated debate.

That’s because it dates back to 129 C.E., and we don’t know what it sounded like. According to CatholicCulture.org, then-Bishop of Rome Telesphorus proclaimed that “In the Holy Night of the Nativity of our Lord and Savior, all shall solemnly sing the ‘Angel’s Hymn.’” As to when exactly the Holy Night of the Nativity occurred, that’s also a little questionable—Reader’s Digest reports that the church didn’t start celebrating Christmas on December 25 until about two centuries later, in 336 C.E.

Though we don’t know the original tune of the “Angel’s Hymn,” we do have an idea of some of its lyrics. In the Bible, the angels responded to Jesus’s birth by saying “Glory to God in the highest,” which, in Latin, translates to Gloria in excelsis Deo. And, even if you don’t celebrate Christmas, you might have heard that particular line on the radio around this time of year: It’s featured in the popular Christmas song “Angels We Have Heard on High.”

In her book Spirit of Christmas: A History of Our Best-Loved Carols, Virginia Reynolds explains that British bishop James Chadwick created the still-popular ditty in 1862 by combining the traditional Gloria in excelsis Deo hymn with a loose English translation of an old French carol called “Angels in Our Fields.”

So, although “Angels We Have Heard on High” in entirety doesn’t exactly qualify as the oldest Christmas song of all time, it definitely helped the original “Angel’s Hymn” gain mainstream, long-lasting recognition. Other early Christmas hymns, like “Jesus Refulsit Omnium” and “Corde natus ex Parentis,” weren’t so lucky.

[h/t Reader’s Digest]