Other than some Christmas hymns, this is possibly the most widely recognized hymn of the last 150 years. The text is adapted from the book of Revelation.
This arrangement starts with the first stanza sung in unison, which is intended to emulate the style of plainsong chant, then repeats the first stanza in three parts a capella. Many groups will be able to sing this long without significant pitch drift, and some others might find it difficult. If pitch drift is a problem, either the acapella unison or a capella parts stanza could be omitted.
The second stanza is accompanied by a flowing arpeggiated accompaniment. The third stanza is a variation on Dykes' tune set in minor key complemented by a somber accompaniment. It soon resolves into a stately final stanza with a moving bass line in the accompaniment.
HOLY, HOLY, HOLY, an arrangement of a hymn by John B. Dykes with lyric by Reginal Heber, arranged by Tom Kirkland for TTB with piano accompaniment, comes in a pdf file of 416K, with a ten-page score and a license page, eleven pages in all. Performance time should be approximately 4:20.