Pope Francis’ brief tour of America brings a real opportunity for the straight- talking pontiff to share an important moral lesson with Washington lawmakers.

The Pope is coming to the United States for the first time in a six-day visit to Philadelphia, New York, and Washington, D.C. His visit will start in Washington, D.C., on Tuesday, and will include a stop at the White House to meet with President Obama, and an address to a joint session of Congress. He’ll also deliver a speech to the U.N. General Assembly in New York and celebrate an open air Mass in Philadelphia that could draw more than one million people. Two hundred thousand people are expected to watch his speech to Congress on large screens along the National Mall.

As a practicing Catholic, I am amazed at how much positive attention Pope Francis is drawing – often from my friends who are not even Catholic – because of his focus on different issues from those that occupied his predecessors. He calls for action on climate change, has strong criticism of the church for its focus on dogma rather than serving the poor, and is outspoken on income inequality and the idolatry of money.

In a recent interview, Stephen Colbert says the most important message that Congress needs to hear from the Pope is about the “corrupting influence of money in politics,” because, “it reinforces not looking out for the least of my brothers.”

Colbert is right. The Citizens United ruling of 2010 has exponentially increased the ability of wealthy individuals and corporations to dominate elections and control the policy agenda in Washington, D. C., and in state capitols around the country. These interests don’t focus on the well-being of the public, but rather on the narrow interests of their own corporate bottom line. The result is an unprecedented gap between the rich and poor, along with a stagnating economy and steep barriers for most Americans to achieve upward mobility.

The Pope travels from the seat of governmental power in Washington, to the seat of financial power in New York, but ends his travels where democracy’s journey began, in Philadelphia. One can hope that he will call the people to action as the Framers did in Philadelphia, while reminding the leaders of government and capitalism that they too are people who should be looking for ways to care for their sisters and brothers left behind in this period of grotesque inequality.

The President and many members of Congress pay lip service to the importance of fixing our broken campaign finance system, but they do little to move comprehensive reform. The Pope should use his visit to Washington to remind Congress and the President that their job is to lead and, as he said to leaders in South America, “Corruption is the plague, it’s the gangrene of society.”