When Grendel first attacks the mead hall, Beowulf watches as the first of his men is grabbed and devoured. The question as to why has been a topic of debate among academics for as long as the work has been studied.

There is no reason clearly evidenced in the work as to why Beowulf "allowed" one of his men to be eaten. In fact, some may argue that it was simply not in Beowulf's power to save that particular man. Indeed, the entirety of Beowulf's character revolves around his heroism and his loyalty to his men, and allowing one of his own to die at the hands of the vicious Grendel would not at all be good display of these traits.

The most common explanation for this is that Beowulf needed to be able to observe Grendel's attack and that, without some observation and foreknowledge of Grendel's abilities, Beowulf would have been unable to retaliate and eventually defeat him.

While it is almost equally difficult to accept in terms of Beowulf's character, he may have been unable to stop the attack at all. It is implied that Grendel's movements were quick, and he must have been to be able to rip down a door without the men having time to be ready. Grendel possesses supernatural abilities that are often vague, unspecified, or even lost in translation, so it is not hard to believe that the initial attack was simply too much for Beowulf to process in time.