I don't see the Light as being Eru Himself but as
proceeding from Him. It is not His manifestation in Arda but rather his 'power' manifesting there. The Light is the Light which the Secret Fire produces. So, I don't have a problem with the Light being visible to the Eruhini, as it is not the Secret Fire itself which would be visible to them, only the 'effect' of it.
This would show that Saruman has misunderstood, or lost touch with, the truth. The Light
may be broken, but not the Secret Fire itself. Saruman seems to have conflated the two. Hence, he has 'left the path of Wisdom'. In the same way, Sauron
could (mis)use the Light, as could Feanor, because none of them would actually be (mis)using the Secret Fire itself, only the 'effect' it produces...
I know I'm 'qualifying' my earlier statements in saying this. I can only say that Kuruharan's points have forced my to think more deeply about this question, for which I'm grateful. Also I would refer my fellow Downers to my new sig.....
