So true. It’s fun to walk around and see what you run across.

Fascinating! Excellent sleuthing, DaddyO. I couldn’t find any information at all on most of the paintings in this church. Thank you for finding and sharing that!

Batoni used oil sketches to confirm his commissions. In 1746 he was tasked with replacing Francesco Vanni’s “Fall of Simon Magus” in St Peter’s Basilica. Batoni’s work, completed in 1755, was removed in 1757 and is now displayed in the Church of Santa Maria degli Angeli in Rome. The Salzburg picture is an authentic sketch made previously, purchased by Count Czernin from the heirs of Saint-Saphorin. The final modello is in the Cleveland Museum of Art, Ohio (inv. no. 83.217). Simon had himself baptised by Philip, and offered St Peter money, that he might receive the Holy Ghost,
but the Apostle refused. Simon’s demonstration of his power of levitation before Emperor Nero – who in Christian art represents the force of evil – is thwarted by St Peter’s prayers. Simon falls headlong from the heavenly zone, where angels and demons are doing battle. St Paul, with book and sword, stands behind St Peter clad in blue and yellow.

https://www.domquartier.at/en/residenzgalerie-collection-online/paintings/the-fall-of-the-magician-simon-sketch-for-santa-maria-degli-angeli-rome/