in beowulf, why does beowulf sail with his chosen companions to hrothgar’s kingdom?

Beowulf sails with his chosen companions to Hrothgar's kingdom primarily to help Hrothgar by destroying the monster Grendel that is terrorizing the kingdom. This journey is motivated by a sense of duty and honor to aid Hrothgar, who had once done a favor for Beowulf's father, and also by Beowulf's desire for glory through heroic deeds. Though Beowulf seeks to win fame and perhaps treasures, the main reason for the voyage is to assist Hrothgar in ridding his kingdom of the menace posed by Grendel.