Divine and arcane magics are totally different. Divine magics are drawn from a deity using their cleric as a conduit, the closer the cleric is to their god (higher the level) the more magic can be drawn. A divine scroll may contain the magic required to cast the spell but you would at least need to be a cleric to read it. As such, a mage would simply be unable to read a divine scroll. It would be completely alien just like a mage scroll would be to a cleric.
There are two exceptions to the rule. (I am aware of)
1) Multiclassed characters (obviously)
2) Scrolls of projection (extremely rare)
Scrolls of projection can be used by anyone with the ability to read the language the scroll is written.
