why does the speaker suggest that his comrade be moved into the sun?

The imagery regarding the sun contrasts its vitality and warmth with its ultimate inability to wake one who has died. In the first stanza the sun is personified and described as "kind" and "old", its warmth ancient and affirming. The speaker is quiet and gently hopeful when he asks that the body be moved into the sun. Many of Owen's poems focus on the bond between man and Nature, and here Nature seems like it could revive the speaker's friend.