Remember that you're reading this poem in translation. In the original Anglo-Saxon text, every line alliterates, as it was this alliteration that served as the primary marker of poetry, rather than, say, rhyme. It is generally thought that this alliteration could assist the scop (pronounced "shope"), or poet, in remembering his poem as he recited it aloud, and certainly it helps to create a memorable swinging rhythm. Because alliteration is consistent throughout the poem, however, we need to be cautious about any inferences we make from alliteration that has been retained in a translation. Sometimes, a translator will attempt to keep the alliteration of the original, but this is not always possible, and it depends upon whether that translator is privileging meaning, mood, or style. The translation you've used here isn't very accurate in terms of what the poem actually says—I'd translate these lines as something more like "it is good and proper for a man to honor his lord (winedryhten) with words and cherish him in his heart when the time comes for that lord to be led out of his body." But my literal translation possibly doesn't capture the tone of the original. I'm sure you can sense the difference—the more poetic translation you've used above has a tone of quiet reverence, a somberness. It uses a rhythm we associate, in modern English, with homilies and sermons; it captures the correct attitude the Anglo-Saxons would have had toward the great hero, Beowulf, and other great fallen warriors. It takes an appropriately respectful, mournful tone toward death and remembrance.