Ulmo's reaction, like Aulë's, is taken from the Book of Lost Tales version of this story.
Nienna's thoughts are more my own interpolation: I see her as the quiet voice of conscience of the Valar, who says things which are often unwelcome to the others (but Manwë, at least, respects her moral insight).
Part 249 Verdict
Next time: Part 250: Sentence
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