I think that The poem “So We’ll Go No More A-roving” is all about love. More specifically, it is about a relationship that went wrong. The first stanza of the poem shows how the poet, Thomas Campion, who wrote the piece in 1817, is clarifying that “We’ll go no more a-roving,” meaning they are not going to hang out anymore. In that same stanza, Campion has mentioned “Though the heart be still as loving” which I interpret to mean that they still love each other but had to break up.
In the second stanza, I googled what a sword symbolizes in poetry, and I learned that it means a phallic symbol. And the sheath means a yonic symbol. Also, in the second stanza I think it means that the poet is exhausted and from the words that are used form the stanza like “ wears out, must pause, have rest.”
In the third stanza, the author uses juxtaposition. In the first line he is mentioning “Though the night was made for loving,” but then in the third line , he restates ” Yet we’ll go no more a-roving” The poet has decided that he ( or they) will not rove any longer, for reasons he’s already explained, even though the night was perfect for it.