Francis then turned to the biblical law that required the payment of tithes, which would be used to assist the poor, people without land, orphans and widows.
He said that tithes such as this arrive daily to the Office of the Papal Almoner, which oversees the Pope's charity funds.
When the letters come in, they frequently contain "a little bit of money: something small or not so small, which is part of a person's salary to help others," the Pope said, explaining that "it's beautiful" to help others, whether it be people, charitable institutions, hospitals, retirement homes or foreigners.
Pope Francis then issued a sharp condemnation of the practice of usury, and lamented how many families have been forced to live on the streets due to the corruption of those who want to line their own pockets.
"Usury is a grave sin before God," he said, and noted that many times, people in desperation "end up committing suicide because they can't do it and they don't have hope."
These people "don't have an outstretched hand to help them, only the hand that makes them pay for personal interests," he said, and prayed that the Lord would use the Jubilee of Mercy as a time to remove the desire of usury from all hearts, making them bigger and more generous instead.
Francis pointed to God's promise to bring blessings to those who lend a hand and who give generously, adding that when we are generous, the Lord "will give you double...maybe not in money, but the Lord always gives double."
He closed his address by encouraging those present to have the courage to share what they have with others. This, he said, "is called mercy, and if we want the mercy of God, let's begin to do it ourselves."