Author Gerald Posner has been investigating the Vatican Bank for years and says every time we get a new pope, we hear more or less the same story: claims of wanting to reform the church's finances.

But Pope Francis, Posner says, is for real.

In advance of the pontiff's trip to New York City, Money Talking host Charlie Herman talks with Posner about his book God's Bankers: A History of Money and Power at the Vatican, and how Francis is trying to reform the institution that has operated like an "offshore bank in the heart of Rome." 

And then, considering that New York City is a center of wealth and power, how will this pope balance the need to raise from money wealthy New Yorkers with his mission to make a church that is "poor and for the poor."