The poem starts with a small shock: during an ordinary dinner, the speaker bites down on a stone. Instead of anger, the moment brings a strange comparison. The stone is "as fresh as an aspersion," a slander or a splash of cold water, depending on how you hear the word. Either way, it's something sharp that arrives without warning.
The second stanza turns calm and a little puzzling. The speaker says the stone will do no harm, then pictures a creature staying in a hole all night. That image suggests hiding, waiting, enduring the dark, perhaps the speaker's own state of mind.
The last stanza names the feeling underneath: the speaker is "full of loss." Yet they love the light, which "is in love with no one." That light is generous but indifferent, shining on everything equally. The mood is quiet, wry and tender, a grief that finds odd comfort in something that asks nothing back. The title's meaning is left open.