FTP, name this Latin title of a brief Henry Wadsworth Longfellow poem and a ten thousand line work of John Gower.
One poem of this name includes a man "In raiment of camel's hair" who is asked if he "Shattered the vessel of clay / In the Valley of Slaughter".  That character asks "Ye scribes, why come ye hither?" and declares that "the wicked shall wail and weep / And be blown like a smoke away" and repeats the line "Repent! repent! repent!".  In addition to that poem written as a conversation between a Priest and John the Baptist, another poem of this name describes the sacking of New Troy and murder of Simon Sudbury.  That poem followed its author's Mirour de l'Omme and allegorically described the Peasant's Revolt of 1381.  FTP, name this Latin title of a brief Henry Wadsworth Longfellow poem and a ten thousand line work of John Gower.
One poem of this name includes a man "In raiment of camel's hair" who is asked if he "Shattered the vessel of clay /
Vox Clamantis