Iam lucis orto sidere, WAB 18

 (Now that the daylight fills the sky), WAB 18, is a motet composed by Anton Bruckner in 1868. The work is also known as In S. Angelum custodem (In the custody of the holy angel). Bruckner revised the composition in 1886.
History.
Bruckner composed this motet in the summer of 1868 for the "" ("Guardian angel confraternity") of Wilhering Abbey. Bruckner dedicated it to Adolf Dorfer, the abbot of the abbey. Bruckner set the music on the text written by Robert Riepl, one of the priests working at the abbey. The motet was performed in the same year in the abbey.
Riepl's text is an adaptation of the text used by Orlande de Lassus. Bruckner's original manuscript, which was stored in the abbey, is lost. A copy of it is stored in the archive of the Kremsmünster Abbey and two other copies are found in the Austrian National Library. The motet was published in 1868 by the Wilhering Abbey.
In 1886, Bruckner made a new version of the motet for men's choir, which was published in the journal "", volume 1, no. 8, p. 240, F. Mamroth, Vienna.
The "" includes two settings of the 1868 version in volume XXI/24, and the 1886 setting in volume XXI/35.
Music.
The first version in Phrygian mode, which Bruckner composed in 1868, is 24-bar long. Two settings are extant: a first with all eight verses of Riepl's text for choir "a cappella", and a second with only one verse of a different text for choir and organ. The motet is a simple, modally inspired piece and homophonic throughout.
A new version of the motet in G minor, which Bruckner composed in 1886, is one bar shorter (23-bar long). It uses verses 1, 2, 7 and 8 of Riepl's text and is set for choir "a cappella".
Selected discography.
The first recording occurred in 1976:
1868 version.
First setting.
A few other recordings, all with deviations from the score:
Second setting.
Only one recording :
1886 version.
There are two recordings of this version: