"The Romish Doctrine concerning Purgatory, Pardons, Worshipping and Adoration, as well of Images as of Relics, and also Invocation of Saints, is a fond thing, vainly invented, and grounded upon no warranty of Scripture, but rather repugnant to the Word of God."
That's the work of someone who knows how to say what they mean.
Jesus wasn't too shabby either:
"You snakes! You brood of vipers! How will you escape being condemned to hell? Therefore I am sending you prophets and wise men and teachers. Some of them you will kill and crucify; others you will flog in your synagogues and pursue from town to town. And so upon you will come all the righteous blood that has been shed on earth, from the blood of righteous Abel to the blood of Zechariah son of Berekiah, whom you murdered between the temple and the altar.
Back when I was in college and was up late studying, I'd head to the commons room and watch Dr. Gene Scott. I was never really sure what he was going on about, but it was fun listening to him rant.
On the modern front, perhaps the best writer of invective today is probably Ann Coulter. If you read her and ignore the issues (which can be hard for some people), you'll find she is rather good at what she does.
What sad is how few of our leaders can use invective. The common reason given for so not doing is that they are too mature. I think that's nonsense. It's not that they will not, it is because they can not.