[Rex noster adveniet Christus quem] Joannes

The missing text can be safely reconstructed, and although no clefs are visible, the melody appears to be that of a 2A gradual. The placemente before the Alleluia also suggests this is a gradual verse. However no such item is found with this text, one that apparently only seems to pertain the Office invitatory for the same day in the year (3rd Sunday of Advent).