The workbox is a box the husband gives his wife to keep her sewing supplies in. He has made it from the same oak that was used to make the coffin of John Wayward. The wife is shocked by the news that John is dead, and the husband seems to enjoy the fact that his gift has had such an effect on the wife. He questions his wife about knowing John, and she denies knowing him, even though he was from his wife's home town. It is in the last stanza that we know that the wife did know John Wayward and has always loved him.
Yet still her lips were limp and wan,
Her face still held aside,
As if she had known not only John,
But known of what he died.
The wife's reaction to John's death is deeper than she wants to admit, and she tries to hide it from her husband.