Gandalf’s Possible Inaccuracy in the chapter “The Shadow of the Past”

[Inziladun]

Originally Posted by Zigûr

As an aside, it strikes me as potentially (but not necessarily) inconsistent that Sauron's spirit was capable of carrying off the One during the drowning of Númenor, but could not do so from Mordor at the end of the Second Age. Why wasn't Isildur grabbing at it out of the air as it slipped off Sauron's severed finger and floated away into the East? Presumably Sauron could no longer achieve feats like this, having expended so much power in creating another body for himself after the last one was drowned.

I see in those two examples a fundamental difference in what was happening to Sauron.

At Númenor, Sauron's physical form was unexpectedly destroyed by the force of the waters inundating the island. His fea was completely intact.

After fighting off Elendil and Gil-galad, and robbed of the Ring by Isildur, his hold not only on his corporeal body but also his very spirit was sudden;y weakened. The shock alone could have rendered him incapable of doing anything to regain the Ring.