Pope Francis declared on Palm Sunday that Christians must not be sad or discouraged but filled with joy because Jesus conquered evil and every sin "with the force of God's love."

"Jesus on the Cross feels the whole weight of the evil, and with the force of God's love he conquers it, he defeats it with his resurrection," he said March 24.

"Dear friends," Pope Francis told the thousands of pilgrims filling St. Peter's Square and the street leading to it, "we can all conquer the evil that is in us and in the world: with Christ, with the force of good!"

The liturgy began with the Pope touring through the crowd in the open-air popemobile and finishing at the obelisk that stands in the middle of St. Peter's Square.

Accompanied by cardinals, bishops and laity holding palms, he listened as the readings were proclaimed. The group of clergy and faithful then made their way to the altar in front of the basilica and heard the reading of the Passion of Christ from Matthew's Gospel.

Pope Francis reflected on three elements in his Palm Sunday homily: the joy that comes from meeting and knowing Christ; the fact that Jesus entered Jerusalem to redeem the world with his loving sacrifice on the Cross; and that young people can teach everyone to embrace the Cross with joy and to live lives of self-sacrifice.

The first word that came to the Pope's mind as he reflected on the entrance of Jesus into Jerusalem was joy.

"Do not be men and women of sadness: a Christian can never be sad! Never give way to discouragement!

"Ours is not a joy that comes from having many possessions, but from having encountered a Person: Jesus, from knowing that with him we are never alone, even at difficult moments, even when our life's journey comes up against problems and obstacles that seem insurmountable," he said.

The Pope then turned to his second point of reflection – the way Jesus entered Jerusalem, as a king who was received "by humble people, simple folk."

But even more, he entered "to receive a crown of thorns, a staff, a purple robe: his kingship becomes an object of derision.

"And this brings us to the second word: Cross. Jesus enters Jerusalem in order to die on the Cross.

"And it is here that his kingship shines forth in godly fashion: his royal throne is the wood of the Cross," he underscored.

What Jesus did, Pope Francis said, was to take upon himself "the evil, the filth, the sin of the world, including our own sin," and cleanse it "with his blood, with the mercy and the love of God."

He then recalled how the world is filled with the effects of evil and sin:

"Wars, violence, economic conflicts that hit the weakest, greed for money, power, corruption, divisions, crimes against human life and against creation! And our personal sins: our failures in love and respect towards God, towards our neighbor and towards the whole of creation."

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In the face of all this, he asked, "Do we feel weak, inadequate, powerless?"

"But," he responded, "God is not looking for powerful means: it is through the Cross that he has conquered evil! We must not believe the Evil One when he tells us: you can do nothing to counter violence, corruption, injustice, your sins!"

"We must never grow accustomed to evil!" he insisted.

"With Christ," he declared, "we can transform ourselves and the world. We must bear the victory of Christ's Cross to everyone everywhere, we must bear this great love of God."

Pope Francis dedicated his final words to the youth, who were in St. Peter's Square today because Palm Sunday is traditionally the day on which World Youth Day is celebrated at the diocesan level.

"Dear young people," he said, you have "an important part in the celebration of faith! You bring us the joy of faith and you tell us that we must live the faith with a young heart, always, even at the age of seventy or eighty."

"And you are not ashamed of his Cross! On the contrary, you embrace it, because you have understood that it is in giving ourselves that we have true joy and that God has conquered evil through love," he told the youth.

Pope Francis also looked ahead to this coming July, when he will participate in his first World Youth Day as Pope.

"Dear friends," he said, "I too am setting out on a journey with you, in the footsteps of Blessed John Paul II and Benedict XVI.

"We are already close to the next stage of this great pilgrimage of Christ's Cross. I look forward joyfully to next July in Rio de Janeiro!" he told the young people in St. Peter's Square.

"I will see you in that great city in Brazil! Prepare well – prepare spiritually above all – in your communities, so that our gathering in Rio may be a sign of faith for the whole world."

Following Palm Sunday Mass, Pope Francis spent around 25 minutes moving through the piazza greeting the faithful – an unusually long time for a segment that typically takes about 10 minutes.