Article I, Section 8: The Delegated Powers
There are more than three powers listed in Article I, Section 8, for sure, but this sampling gives a sense of how powerful the institution is.
"The Congress shall have Power To lay and collect taxes...
and
"...borrow money on the credit of the United States."
"The Congress shall have the power to... declare war..."
This has empowered Congress further than some expected when the Constitution was drafted in 1787.
Congress may "regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes."