The Fed is “bordering on going too far and possibly tipping the economy into recession,” Mr. Bullard said. He added that other Fed officials were coming around to his position that the Fed should pause.

The Fed at its December meeting raised its benchmark rate into a range between 2.25 and 2.5 percent. It was the fifth consecutive quarterly increase. Mr. Powell said the rate now stood near the lower end of the range that the Fed regards as neutral territory — neither encouraging nor discouraging borrowing and economic growth.

At a news conference after the December meeting, Mr. Powell emphasized that economic growth remained strong, and that the Fed expected to continue raising rates in 2019. Investors registered their disapproval by driving down asset prices, exacerbating a market slump.

Since then, Mr. Powell and other Fed officials have sought to deliver a more nuanced message, emphasizing that they are paying attention to investors’ concerns, and that the absence of inflationary pressure means the Fed can afford to postpone judgment.

The account of the December meeting reinforced that message.

The Fed, according to the minutes, said that “participants expressed that recent developments, including the volatility in financial markets and the increased concerns about global growth, made the appropriate extent and timing of future policy firming less clear than earlier.”

The Fed’s own economic outlook remains upbeat. The minutes described economic data in the final months of 2018 as even stronger than the Fed had expected. Mr. Rosengren said consumers remained “willing to spend,” and he expected unemployment would continue to fall.

Mr. Evans said he was still forecasting “another good year in 2019.”

But uncertainties have piled up in recent months. The minutes said investors were particularly concerned about trade tensions between the United States and China, and about global growth.