Senior Israeli officials have welcomed President-elect Donald J. Trump’s demand that hostages taken in the Hamas-led attack on Israel be released from Gaza before his inauguration in January, and his threat that there will be “hell to pay” in the Middle East if they are not.

Mr. Trump’s social media post on Monday did not elaborate on what action would be taken if the hostages are not released by Jan. 20, when he will be sworn in. Still, some Israeli officials appeared to be reassured by Mr. Trump’s remarks, which suggested the onus was more on the militants holding the hostages than on Israel to free the captives.

“Thank you and bless you Mr. President-elect,” President Isaac Herzog of Israel said in a post on social media. “We all pray for the moment we see our sisters and brothers back home!”

Mr. Herzog’s position is largely ceremonial. Prime Minister Benjamin Netanyahu, seen as the main Israeli decision maker in the war against Hamas in Gaza, has not publicly commented on Mr. Trump’s remarks, nor have leaders of the Israeli military.

Mr. Trump wrote on his Truth Social platform on Monday that “there will be ALL HELL TO PAY in the Middle East, and for those in charge who perpetrated these atrocities against Humanity,” if the hostages aren’t released before his inauguration.

“Those responsible will be hit harder than anybody has been hit in the long and storied History of the United States of America,” he said. “RELEASE THE HOSTAGES NOW!”