You can't afford to not own gold," Jim Cramer told viewers of his "Mad Money" TV show Monday.

After advising viewers to sell 20% of their portfolios on Friday, Cramer said it's time to put that money into gold stocks such as Agnico-Eagle Mines (AEM Quote - Cramer on AEM - Stock Picks), Barrick Gold (ABX Quote - Cramer on ABX - Stock Picks) or an ETF that mimics the price of gold.

Cramer told viewers that they simply "must own gold" in times of uncertainly. With the fate of Treasury Secretary Henry Paulson's financial bailout plan still uncertain in Congress, he said he cannot endorse a portfolio that does not include a gold stock.

Cramer said owning gold makes sense whether the Paulson plan succeeds or fails. If it fails, he said, the financial system will completely freeze up, leaving gold as the only safe harbor. In a market where treasuries and cash pay almost nothing, gold will be the only trustworthy place to store value, he said.

On the flip side, Cramer said if the Paulson plan does pass Congress, investors need to be concerned about inflation. With the government issuing so much new currency, inflation will be inevitable and gold will perform well. Either way, he said, gold is where investors will want to be.

Cramer said the fundamentals for gold are strong, with worldwide demand for gold still increasing across the globe. Cramer said even in the worst case situation, gold stocks will still make investors money although they may underperform the market.

"Gold makes sense when nothing makes sense," said Cramer.