The letter B contains a colourful image of the Trinity in the iconography known as the Throne of Mercy, God’s mercy seat or Throne of Grace. God the Father is depicted with a tiara, wearing an opulent red robe over a purple dress. He is seated in heaven on a throne, shimmering with light. God the Father supports the Cross with the body of Christ, the son, while above, the Holy Spirit, in the form of a dove, hovers in golden light, radiating as tongues of fire. The Christian doctrine of the Trinity defines God as three persons: the Father, the Son, and the Holy Spirit.
Five, large putti are frolicking around in the border decoration, their wings coloured in blue, green, and red. The smaller putti are nude, but the two larger ones are dressed and make themselves useful: one presents the initial and the other one the cartouche, saying 1550, the year of origin. In the lower margin, two putti are bouting around with joisting sticks. The decoration on this leaf is of high quality and the smooth, effortless brushstrokes suggests the hand of a professional illuminator. Presumably, he was linked to the Glockendon workshop in Nuremberg. This was a famous family related workshop of (grand)father, sons and grandsons which continued their activities until c. 1575 – with Sebastian Glockendon as the last known illuminator.
The leaf contains text and music for the Responsorium sung at the Feast of Trinity Sunday, Benedicat nos deus deus noster benedicat nos (Ps. 66, v.7-8, O bless our God, ye people, and make the voice of his praise to be heard). Trinity Sunday, the first Sunday after Pentecost is a feast of joy and thanksgiving.
As the year 1550 is quite late for writing and painting books by hand, the provenance likely points to an monastic environment in Southern Germany where such books were still in demand.