1 Whose case when the careful dwarf had told,
careful > {Full of care, wary}
2 And made example of their mournful sight
example > warning
3 To his master, he no longer would 4 There dwell in peril of like painful plight, 5 But early rose, and, ere that dawning light
ere that > [before the]
6 Discovered had the world to heaven wide,
Discovered > Revealed
7 He by a privy postern took his flight,
privy > secret, hidden postern > {Back door or gate; any door distinct from the main one}