What Does it Mean?
When someone says that something “would take an act of Congress” to happen, they are telling you that it is very unlikely or would be very difficult to do.
I hear this often, and although it mentions Congress, it is used in any conversation. The meaning behind it is a reference to the fact that the US Congress is slow to make change and it is very hard to get changes made in Congress. Many times it takes years, if not decades, before an issue even has the chance to be heard by the Congress.
Simply put, you are saying that something is nearly impossible to do.
Ways This is Used
A couple of simple examples where you might hear this phrase used:
“It would take an act of Congress to get Bill to clean out that garage.”
“It would require an act of Congress for Tina to give him the job back.”