Let all mortal flesh keep silence
This powerful and moving hymn is based on the Prayer of the Cherubic Hymn from the Liturgy of St James (4th century), one of the earliest extant liturgies of the Christian Church, and is found in both Greek and Syriac. It is still in use among Orthodox Christians, who recite it in Jerusalem on the Sunday after Christmas. The prayer is chanted by the priest at the Great Entrance, a dramatic moment in the Eucharist when the elements of bread and wine are brought into the sanctuary. The whole liturgy was first translated into English by J M Neale and R F Littledale and published in their Translations of the Primitive Liturgies (1868-69). The translation by Gerard Moultrie (1829-85), an Anglican priest, appeared in Lyra Eucharistica and The English Hymnal (1906). Biblical references include in verse 2, John 6:51, in verse 3, John 1:5,9, and in verse 4, Isaiah 6:1-3, Revelation 4:8, and Revelation 19:1-6.
Tune - Picardy
Picardy is a French carol melody, perhaps as old as the 17th century, although not traceable earlier than the 19th century in Chansons populaires des provinces de France (1860) with the title "La Ballade de Jesus Christ", and in Tiersot's Mélodies (Paris, 1887) with the title "Romancero". Inclusion in The English Hymnal (1906) to the words "Let all mortal flesh..." was followed by inclusion in Hymns Ancient and Modern (1939) where it was used as the setting for "Sing, my tongue, the glorious battle" (this is more commonly set to Pange Lingua).
When sung slowly it has a sombre but also dignified and ceremonious character. Sung fast, the sombreness changes to fierceness. This dual personality is remarkable, and can be attributed to an unusual character, with a striking rhythm alternately hastening and halting.