The first stanza is talking about death and that there is a place of peace for the heart to sleep. The second stanza is explaining the peace of that place and that there is no sadness or greif. The third and final stanza talk about how there is nothing to do in this place and that the job is done
The similes marked in the poem describe things that the rest he is in is like. which is major important along with the Visual words he uses because that let everyone see this sure haven of rest as he puts and just imagine the peace there. Which is his intentions i believe.