"The root of all sin" is thinking that one is god, something often expressed in a total preoccupation for accumulating money and power, the pope wrote. And just as individuals can be tempted to think they have no need of God, social and political systems can run the same risk, ignoring both God and the real needs of human beings.

"Love alone is the answer to that yearning for infinite happiness," Pope Francis wrote. It is the only response to the longings "that we think we can satisfy with the idols of knowledge, power and riches."

As he advised a year ago, Pope Francis reiterated that Lent is not just about giving up the soda, video games or anything else personal per se. The bigger picture is partaking in giving and doing good for others.

But Pope Francis has asked us to reconsider the heart of this activity this Lenten season. According to Francis, fasting must never become superficial. He often quotes the early Christian mystic John Chrysostom who said: “No act of virtue can be great if it is not followed by advantage for others. So, no matter how much time you spend fasting, no matter how much you sleep on a hard floor and eat ashes and sigh continually, if you do no good to others, you do nothing great.”