The speaker sets out searching for joy and finds it, or something like it, in a garden. The walk through an ordinary park becomes an attempt to enter a different place, an "inward park," which seems to mean a state of mind or inner space rather than a real location. The effort is clear in the word "endeavoring": this isn't a casual stroll, and the speaker has to work to get there.
The last two lines are the most puzzling. The speaker wants to "carry people over / through the common bed," which suggests helping others cross into this inner calm too. A "common bed" could be a flower bed shared by everyone, and the word "common" hints that joy is available to all rather than reserved for a few. The mood is quiet, hopeful, and a little tentative. Nothing is fully resolved, but there's a gentle sense of generosity, as if finding joy matters more when you bring others along.