Acceptance of mythology?

[Lush]

Those who get their power from Eru use it for good.

Not neccessarily, darling. Galadriel's motivation was ambiguous and she didn't redeem herself for a long time. Fëanor screwed up his great potential and plunged his own kind into darkness and despair. Shall I even get into Turgon and how his pride caused the demise of his people?

All of the above, characters, I would argue, received their gifts from Eru.

See, it's not as black and white as your above statement would have me believe.