If I say: My bed shall comfort me, and I shall be relieved speaking with myself on my couch:

When I said, 'My bed doth comfort me,' He taketh away in my talking my couch.

When I say, My bed shall comfort me, my couch shall ease my complaints;

When I say, In my bed I will have comfort, there I will get rest from my disease;

If I say, "My bed will comfort me, and I will find rest, speaking with myself on my blanket,"

When I say, My bed shall comfort me - The idea in this verse and the following is, that there was no intermission to his sorrows. Even the times when people usually sought repose were to him times of distress. Then he was disturbed and alarmed by the most frightful dreams and visions, and sleep fled from him.
Shall ease my complaint - The word rendered "shall ease" ישׂא yı̂śâ' means rather, shall bear; that is, shall lighten or sustain. The meaning is, that he sought relief on his bed.

When I say, my bed shall comfort me,.... When he thought within himself that he would lie down upon his bed and try if he could get a little sleep, which might comfort and refresh him, and which he promised himself he should obtain by this means, as he had formerly had an experience of:
my couch shall ease my complaint; he concluded, that by lying down upon his couch, and falling asleep, it would give some ease of body and mind; that his body would, at least, for some time be free from pain, and his mind composed, and should cease from complaining for a while; which interval would be a relief to him, and of considerable service. Some render it, "my couch shall burn" (h); be all on fire, and torture me instead of giving ease; and so may have respect to his burning ulcers.
(h) "ardebit", Pagninus; so Kimchi in Sepher Shorash. & Ben Melech in loc.