Curse of Túrin

[William Cloud Hicklin]

From the exerpt from Osanwe-kenta:

Turin, Morwen and Nienor were willful and prideful. But these traits were subject to the influence of Morgoth, at least when his attention was focused upon them.

And that I think encapsulates my view: the "curse" was Morgoth's ability to amplify the worst aspects of the target's nature. This is actually not unlike the operation of the One Ring in a later age. Morgoth didn't make Turin build the bridge at Nargothrond, but he made him arrogant (or more arrogant); he didn't make Turin hound Saeros to his death, but he made him wrathful and hot-tempered (or moreso). This is generally assumed among Christians (and I believe Jews) to be the usual way in which diabolic temptation works- qv The Screwtape Letters- which JRRT disliked, but ironically were dedicated to him.

That Morgoth could act as the Tempter, capital-T, can be seen in Tolkien's offstage but unmistakable allusion to the Eden story, especially the Tale of Adanel.