Why did the monsters get "punished" in beowulf?

Because they are the descendants of Cain

Explanation:

Beowulf is an epic poem that is considered one of the most important works written in Old English. It tells the story of a hero called Beowulf, who faces a monster called Grendel in 6th century Scandinavia.

The monster Grendel is considered to have been "punished by God." The reason for this is of Biblical origin. Grendel was punished by God because he is supposed to be a descendent of Cain. Cain is a biblical figure who is responsible for murdering his brother out of jealousy. This horrible crime led God to curse his lineage, making him the father of all monsters, including Grendel.

the factors that the economies of the muslim empires prosper were:

1- land trade routes-located between three continents  

2- sea trade routes

trade contributed to the spread of muslim empires, and with that islamic culture led to a growing feeling of internationalism resulted in the transfer of technology, science, and other cultural forms.