The Quran doesn't have the Abrahamic monopoly on cruelty. The old testament has far crazier shit in it. Quaran, for example doesn't suggest death for wearing cotton and silk at the same time.
[citation needed]
The OT does not suggest death for mixing wool and linen (not cotton and silk). It says not to do it - but doesn't give a penalty. And considering the OT is pretty clear on when the death penalty
is applied, I'd say it wasn't to be applied for mixing wool and linen.
There's several theories as to why that particular command was there:
- The outfit of the priests included a linen garment and and woolen garment. Much like how people today aren't allowed to dress up as a police officer, it's possible this was to stop people from dressing up in the outfit of a priest to impersonate them.
- To set the Israelites apart from the Caananites:
These and other prohibitions were designed to forbid the Israelites to engage in fertility cult practices of the Canaanites. The Canaanites believed in sympathetic magic, the idea that symbolic actions can influence the gods and nature…. Mixing animal breeds, seeds, or materials was thought to “marry” them” so as magically to produce “offspring,” that is, agricultural bounty in the future.
- Or simply because wool and linen don't mix in the same garment. They'll shrink different after you wash them and become messed up. So it simply may have been essentially a practical fashion tip.
Anyway, the point is there was no death penalty associated with it.