My priest has a weapon in one hand and nothing in the other hand.

When I select a spell that targets an enemy ( I chose Pillar of Faith ) and right click to see the description, it shows the +12 bonus for using a single weapon. I wanted to test if this is true and casted the spell on the amphoras in the room. To my disappointment, no attack roll was shown in the combat log. But the spell had this green glowing that circles around it ever since. I have my wizard cast fan of flames. The green glow was there while she was casting, but it disappeared after finishing casting. The main difference was that fan of flames did not hit a target, because all targets in the room were already destroyed. The only way to get rid of the green glow of Pillar of Faith was to load the last save.

 

https://imgur.com/a/WsazY

OK, I tried again and loaded a save where the amphoras are still there.

 

https://imgur.com/a/HPJHD

 

The wizard destroys the amphoras with fan of flames, you see an attack roll and damage and the green glow disappears after casting.

The priest has the same effect as before. This is the only priest spell I have that causes damage, so I do not know if the problem is the spell or the priest.