Four months after Jon Stewart passed the torch to Trevor Noah, the former host of "The Daily Show" returned to his old stomping ground for the first time. Stewart made a surprise appearance to support a cause that is very close to his heart, the James Zadroga 9/11 Health and Compensation Act, a piece of legislation that would make sure 9/11 first responders get the proper benefits and medical care they deserve.

"Oh, wait, wait, wait, s--t," said Noah upon first seeing Stewart. "Are you here to take the show back? I heard about this in American TV."

Stewart reassured him that he did not want his old job back and then explained his appearance: "I have this issue I care about very deeply and I was wondering.... I want to get attention paid to it, but I was realizing I don't have a show, and nobody gives a s--t anymore. So I thought, you have a show, and maybe I could come and..."

With the platform granted, Stewart took over the next two segments of the show to shed further light on his cause. He even showed footage of him attempting to lobby members of Congress in Washington, D.C., to help get the act passed.

"It's soon going to be out of money," said Stewart of the Zadroga Reauthorization Act, which will expire by next October unless it is renewed, according to the New York Times. "These first responders, many sick with cancers and pulmonary disease, have had to travel at their own expense to Washington, D.C., hundreds of times to plead for our government to do the right thing."

"Of course, there was no reason not to renew it permanently, but they did not renew it anyway!" explained Stewart.

"The only conclusion I can draw is that the people of Congress are not as good a people as the people who are first responders," he declared.

In the second segment, Stewart put the blame for the hold up of the Zadroga Act on House Speaker Paul Ryan and Majority Leader Mitch McConnell. He then wanted to revisit a four-person panel he held with 9/11 first responders on "The Daily Show" in 2009, but only one of them was well enough to appear last night as two were seriously ill and the other had passed away.

Watch Stewart's return as a "Senior Correspondent" below.