This is a title-page picture for the Pentcost Sunday, Year C: it is based on the readings from the Roman Catholic lectionary.
It is part of the Sunday-cover-page series, based on an an art-work which is in the public domain: It can be used freely, with no concerns about copyright.
Artwork
Horizontal: adapted from Pentecost by Italian painter
Duccio di Buoninsegna (1255–1319)
Vertical: adapted from Descent of the Holy Spirit, by Greek
painter, sculptor and architect, Doménikos Theotokópoulos aka El Greco
(1541-1614)