Pope Francis warned pilgrims to Rome on Wednesday that God’s mercy is available only to those willing to forgive other people.

All of us need forgiveness, the pope insisted in his weekly General Audience in Saint Peter’s Square, and there is no sin that cannot be forgiven, but a willingness to forgive others is a necessary condition to receive God’s pardon.

Finishing a series of reflections on the Lord’s Prayer, Francis said that the petition “Forgive us our trespasses as we forgive those who trespass against us” has strings attached.

The petition could have stopped with the first part and it would have been very nice, the pope said. “Instead, Jesus completes it with a second expression that is united with the first. The relationship of vertical benevolence on the part of God is refracted and is called to be translated into a new relationship that we live with our brothers and sisters: a horizontal relationship.”

“The good God invites us to be all good,” he continued. “The two parts of the invocation are tied together with a merciless conjunction: we ask the Lord to forgive our debts, our sins, “as” we forgive our friends, the people who live with us, our neighbors, the people who have treated us unkindly.”

God’s abundant grace “is always challenging,” he said. “Those who have received much must learn to give much and to not hold back for themselves what they have received. Those who have received much must learn to give much.”

The pontiff noted that immediately after giving the text of the “Our Father,” Jesus goes on to emphasize the aspect of fraternal forgiveness. “For if you forgive other people when they sin against you, your heavenly Father will also forgive you. But if you do not forgive others their sins, your Father will not forgive your sins,” Jesus says.

It can be terribly hard to forgive, Francis acknowledged, “but if you do not forgive, God will not forgive you. You close the door.”

Even in this, however, God is prepared to lend us a hand, he proposed.

“If you cannot bring yourself to do it, ask the Lord to give you the strength to do it: ‘Lord, help me to forgive,’” he said. “Here we find the bond between love of God and love of neighbor. Love calls for love, forgiveness calls for forgiveness.”

The pope also recalled another gospel parable where a servant is pardoned an enormous debt by his master but then refuses to pardon the debt of a fellow servant who owes him a mere fraction of what he himself owed.

When the master finds out what he has done, he calls the servant back and condemns him. “Because if you do not strive to forgive, you won’t be forgiven; if you do not strive to love, you will not be loved either,” Francis said.

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