The 3 Rings

[Novlamothien]

It was on Amon Hen, when Frodo was fleeing from Boromir. The quote reads thusly

Then as a flash from some other point of power there came to his mind another thought Take it off! Take it off! Fool, take it off! Take off the Ring!

Then, in TTT, when Aragorn &co meet Gandalf aganin he alludes to the fact that he was the speaker of the words. I think that when the Ring was on it gave him the ability of osanwe, but did not know it, and, taking Galadriel's advice, did not try too hard to get it. But that's just my two cents.

Namarie
Erin