I was informed this is another scene (several are represented in the church) from the passion of Saint Gregory the Illuminator. This scene is to the left of the scene with a tree, on the same level where to its right is the scene of the saint with chained feet.

The soldiers of king Tradt are flagellating him. He is also inhaling the fumes from the fire that is burning below his head. There is another fresco, also of the saint hung upside down, but elsewhere in the church.