I saw a star fall from Heaven, and to him was given the key of the bottomless pit…the angel of the bottomless pit, whose name in the Hebrew tongue is Abaddon.@Revelation 9:1,11
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Angel with the Key to the Bottomless Pit
Albrecht Dürer (1471-1528)

Rhabanus Maurus (776-856) (Tibi Christe, splendor Patris); translated from Latin to English by John M. Neale, Mediæval Hymns, 1851.

Unser Herrscher Joachim Neander, 1680 (🔊 pdf nwc).

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Rhabanus Maurus (776-856)

Thee, O Christ, the Father’s splendor,
Life and virtue of the heart,
In the presence of the angels
Sing we now with tuneful art,
Meetly in alternate chorus,
Bearing our responsive part.

Thus we praise with veneration
All the armies of the sky;
Chiefly him, the warrior primate,
Of celestial chivalry,
Michael, who in princely virtue
Cast Abaddon from on high.

By whose watchful care repelling—
King of everlasting grace—
Every ghostly adversary,
All things evil, all things base,
Grant us of Thine only goodness,
In Thy paradise a place.

Laud and honor to the Father,
Laud and honor to the Son,
Laud and honor to the Spirit,
Ever Three, and ever One,
Consubstantial, co-eternal,
While unending ages run.