Elon Musk once called the Wall Street short sellers betting billions on Tesla's failure "jerks who want us to die," and described their campaign against the company as "hurtful." Well, today it's the short sellers who are hurting, and Musk who is celebrating.

Tesla posted a surprisingly strong quarter Wednesday evening, showing revenue of $6.3 billion and adjusted earnings of $1.86 per share versus expected losses of 42 cents per share. That's great news for Musk, who ended Thursday $2 billion richer thanks to the stock's steep rise, and bad news for his nemeses, the short sellers, who lost a collective $1.4 billion.

Musk's $2 billion day

How did Tesla pull this off? As Business Insider explains, it wasn't by raking in more money. Revenue for the third quarter of 2019 was down nearly a billion dollars compared with the same quarter last year. Instead, Tesla tightened its belt. "Tesla used the oldest trick in the business book. It cut its way to profitability," reports the site.

Some analysts argue that isn't exactly the playbook of a business with phenomenal growth ahead of it. As BI notes, "$6 billion to $7 billion in revenue every three months, a meager profit, endlessly refinanced debt to cover the operating gaps. That doesn't really look like a world-beater. It looks like a steady-state sort of business that should in no way be worth more than $50 billion."

But whether or not Tesla becomes a world-beater (and there are other more hopeful signs, like a new Chinese factory built in a record-beating 168 working days), Musk is personally doing just fine. He holds 22 percent of Tesla's stock, which means yesterday's rally netted him a tidy $2 billion in additional net worth. How was your Thursday?

There is one (not exactly tiny) catch, though. "To cash in his options, Musk must approximately double Tesla's market capitalization to $100 billion (at a minimum). Yesterday's earnings report puts him around halfway to that goal," Quartz points out.

So as of now, this money is on paper only. If Musk wants to get his hands on the money, he'll need to get the company's worth up to double what BI suggests might be natural for it. But that's a worry for another day. Right now he's got another reason to celebrate.

Short seller schadenfreude

As anyone who follows him on Twitter knows, Musk has been outspoken about his hatred of the short sellers who bet against his company's success. Tesla is the second-most shorted company in the U.S. market (Apple is number one). So Tesla's impressive Thursday must have been even sweeter thanks to a bit of schadenfreude. While Musk's net worth shot up, the short sellers got creamed.

"Short-sellers, who aim to make money by wagering that a stock will fall, lost $1.4 billion as Tesla shares soared as much as 20 percent, according to data from the financial-analytics provider S3 Partners. The losses erased almost 70 percent of Tesla short-sellers' gains for the year," reports Market Insider.