The book. “Moment” as in a short span of time before he started fantasizing, I believe it was when Frodo was unconscious before the arrival of the orcs and the realization that he was alive, though I’m prone to misremembering. He caught himself in his folly and did great deeds, I just wanted to emphasize how immediate and potent the effect was not to downplay Frodo’s deeds and sacrifice.

Gandalf did touch it in the book, that part was the movies, though he wouldn’t take possession of it, even temporary.