Although “Mad Money” host Jim Cramer sparked controversy on Tuesday when he expressed skepticism for Arena Pharmaceuticals’ stock, he defended his position on Wednesday’s program and reminded investors that “nobody ever got hurt taking a profit.”

Cramer’s controversial comments on Arena Pharma came during Tuesday’s show, as he shared the results of a poll in which viewers voted on the leading stock of the second quarter that they thought could finish strongest in the second-half of the year. The viewers picked Arena Pharma’s stock, which had rallied more than 500 percent going into the poll.

“So I proceeded to give you a couple of heads up about why it might be wise to ring the register in Arena given the huge gain and the possibility of competition, as well as the overall prospects of both the drug, which could be good, and the company, which might not be as good considering its revenue sharing arrangements,” Cramer said.

Cramer knew his stance on Arena had caused backlash, though, when his Twitter account “lit up like a Christmas tree.”

“But you know what? This is a teachable moment,” Cramer said. “It gives us a chance to talk about the fallacy of being married to stocks, the mistake of falling in love with these pieces of paper and the need to be more skeptical of everything involving the stock market if you don't want to end up jilted or crushed and ultimately lose a ton of money.”

To start, Cramer said investors should never blindly root for a stock. Instead, he thinks investors should seek out differing opinions, including both the bear and bull cases. Never stop challenging your thesis about any given stock, he said.

Second, Cramer reminded viewers that any given stock is part of the overall stock market. Almost all stocks are correlated with the broader averages, he said. When a piece of news drives the market, as the U.S. Federal Reserve’s meeting minutes did on Wednesday, Cramer said no individual stock is going to be able to avoid that “gravitational pull.”

Cramer said the most important lesson for investors, though, is that “nobody ever got hurt taking a profit.” If an investor gets a huge gain on a stock, Cramer thinks it’s wise to take some off the table. In his opinion, gains are just too hard to come by. He recommends taking advantage of the gains, instead of hoping for the possibility of even more gains, which may or may not come.

Anyone who owns Arena should make sure to have a diversified portfolio, Cramer said, which includes a utility, a food company, a high-yielding industrial and a dividend-paying pharmaceutical. Cramer said Arena should be their speculative entry, though, not the pharma entry. It’s just too different. (RELATED: Cramer’s 5 Recession-Resistant Stocks)

Either way, Cramer said Arena shareholders should take some profits as they come in.

“Your ultimate goal should be to ring the register on your initial investment so you can play with the house's money, which is why I was so adamant last night that people with big gains in Arena simply must ring the register on at least some, if not all of their profits,” Cramer said. “Playing with the house's money is the holy grail of investing because no matter what happens, you cannot lose money because you're playing with pure profit.”

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