What the heck Gandalf you can't just go shouting Black Speech in Elrond's house. God.
I just reread The Fellowship of the Ring and oh geez, Gandalf is just a giant troll. There they are in Rivendell, one of the last peaceful havens, and Gandalf busts out Black Speech when he very easily could have just spoken the translation, and scared the crap out of everyone.
Elrond pretty much goes "what in the actual hell Gandalf" to which Gandalf replies, "not even sorry. Deal with it."
Gandalf, seriously, you can't do that around elves.
Some of the text (pretty sure you can tell which) is from The Fellowship of the Ring and belongs to J.R.R. Tolkien. Used in a very obvious silly parody here