In this scheme, the Amesha Spentas are the arch-angel retinue of God, with the hamkars as the supporting host of lesser angels.
From the en.wikipedia.org
Incorporating elements of a full-blown sonata scheme within a single, all-encompassing arch, it stands as a fitting conclusion to Brahms'greatest achievement as a symphonist.
From the npr.org
The cycle may have been part of a larger scheme of decoration which once included the outer face of the arch and the other walls of the church.