The Oxyrhynchus hymn (or P. Oxy. XV 1786) is the earliest known manuscript of a Christian hymn to contain both lyrics and musical notation. It is found on Papyrus 1786 of the Oxyrhynchus papyri, now kept at the Papyrology Rooms of the Sackler Library, Oxford. The manuscript was discovered in 1918, and later published in 1922. The hymn was written around the end of the 3rd century AD.
The music is written in Greek vocal notation. It is entirely diatonic, with an ambitus of exactly an octave from F to F an octave above, and a final nominally on G (assuming a key signature without sharps or flats). The notation is Hypolydian, and employs the rhythmic symbols macron (diseme), leimma + macron, stigme, hyphen, and colon. The text is largely set syllabically, with a few short melismas. The hymn's meter is essentially anapaestic, though there are some irregularities.
This hymn is the only surviving fragment of notated Christian music from the first four hundred years of the Christian period, although historian and musician Kenneth Levy has argued that the Sanctus melody best preserved in the Western medieval Requiem mass dates from around the fourth century. It is similar to the hymn in its largely syllabic texture and diatonic melody, with slight differences.[vague]
Modern recordings of the hymn have been included on a number of releases of Ancient Greek music.
The Phos Hilaron and the Oxyrhynchus hymn constitute the earliest extant Christian Greek hymn texts reasonably certain to have been used in Christian worship, but are neither drawn from the Bible nor modeled on Biblical passages.
1 . . . together all the eminent ones of God. . . 2 . . . night] nor day (?) Let it/them be silent. Let the luminous stars not [. . .], 3 . . . [Let the rushings of winds, the sources] of all surging rivers [cease]. While we hymn 4 Father and Son and Holy Spirit, let all the powers answer, "Amen, amen, Strength, praise, 5 [and glory forever to God], the sole giver of all good things. Amen, amen." 
- Hunt and Jones 1922.
- Pöhlmann and West 2001, 192.
- McKinnon 2001.
- Pöhlmann and West 2001, 190–91 and 192.
- Pöhlmann and West 2001, 192–93.
- Smith 2011, 28.
- Levy 1958–62.
- Smith 2011, 211.
- Cosgrove 2011, 37
- Cosgrove, Charles H. 2011. An Ancient Christian hymn with Musical Notation: Papyrus Oxyrhynchus 1786. Mohr Siebeck. ISBN 978-3-16-150923-0
- Hunt, Arthur S., and H. S. Jones. 1922. "Christian Hymn with Musical Notation". In The Oxyrhynchus Papyri, edited by Bernard P. Grenfell, Arthur S. Hunt, E. Lobel et al., 15:21–25. London: Egypt Exploration Fund.
- Levy, Kenneth. 1958–62. "The Byzantine Sanctus and its Modal Tradition in East and West". Annales Musicologiques 6: 7–67.
- McKinnon, James W. 2001. "Christian Church, Music of the Early. §II: Special Issues, 8. The Musical Character of Early Christian Song". The New Grove Dictionary of Music and Musicians, edited by Stanley Sadie and John Tyrrell. London: Macmillan Publishers.
- Pöhlmann, Egert, and Martin L. West. 2001. Documents of Ancient Greek Music: The Extant Melodies and Fragments. Oxford: Clarendon Press. ISBN 0-19-815223-X.
- Smith, John Arthur. 2011. Music in Ancient Judaism and Early Christianity. Farnham and Burlington: Ashgate Publishing, Ltd. ISBN 9781409409076 (cloth); ISBN 9781409421610 (ebook).
- West, M[artin]. L[itchfield]. 1992. Ancient Greek Music. Oxford University Press. ISBN 0-19-814975-1
- Ensemble Kérylos a music group directed by scholar Annie Bélis and dedicated to the recreation of ancient Greek and Roman music. 1996. "Hymne chrétienne d'Oxyrhynchus." Musique de l'Antiquité grecque. K617.069.
- Atrium Musicæ de Madrid, Gregorio Paniagua. 1979. "Christian Hymn of Oxyrhynchus." Musique de la Grèce Antique. Harmonia Mundi (France) HMA 1901015. Arles: Harmonia Mundi.
- Christodoulos Halaris. 1992. "Hymn to the Holy Trinity". Music of Ancient Greece. Orata ORANGM 2013. [Greece]: Orata Ltd.
- Ensemble De Organographia. 1995. "Christian hymn, Anonymous (3rd c. AD) Oxyrhynchus papyrus 1786." Music of the Ancient Greeks. Pandourion PRCD1001. Oregon City: Pandourion Records.