You cannot passively fight aggression. There are all sorts of things the Zoroastrians could have done to fend them off, but didn’t. For every nudge from the Muslims, you have to nudge back, harder enough to leave them wincing.
You equip all women with short knives. Any Muslim comes too close and they are obligated to nick him. Just a small cut will do, at first. Then have them start using pork fat as a hand cream, spraying it around in the presence of Muslims while loudly talking about how good it is for the skin.
Spill pork fat on the streets and sidewalks, cook with it, the smoke and smell permeating the neighborhood. Raise pigs and dogs, and use their excrement as fertilizer on your fields, accidentally dumping quantities of it on Muslim streets and lands.
Set up neighborhood watches so that if a Muslim comes near everybody is ready for them. Make them want to leave.
I agree with you all the way. One goal I have is to get a large pig as a pet. Lots of pigs grow to be like 450 pounds of solid muscle. Then take him for walks, to the lake swimming and so on.