"To those who tortured us, am glad my heart has found love, forgiveness, peace and joy. They are all forgiven because Jesus Christ broke the power of death by suffering on the Cross," Emmanuel said.
After listening to these testimonies "with great pain in my heart," Pope Francis spoke on the meaning of negative experiences and suffering.
Reflecting on Winnie's testimony, the Pope explained that Jesus can perform "great miracles" in life.
"A wall can be transformed into a path towards the future," he said. "There's always the possibility of opening a door, a horizon to the future, and to open it through the Power of Jesus."
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"Winnie transformed her depression and bad experiences into hope. This isn't magic. This is the work of Jesus Christ, because Jesus is Lord. Jesus can do everything."
The pontiff said Jesus had experienced the greatest sufferings in history, having been "insulted, rejected, and murdered," but was Risen from the dead.
"He can do the same in us with every single thing that we experience, because Jesus is Lord."
Pope Francis turned his reflection to the witness given by Emmanuel who managed to escape from a brutal captivity.
"A light is like a seed. In order to live, we have to die. And dying sometimes like Emmanuel's friends – Dying as Charles Lwanga died, and the martyrs – but, through that death there is light for all.
"If I can transform the negative into positive, I am triumphant in the Lord. But, that can only be done with the grace of Jesus Christ."
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The Pope then issued a challenge to the young people present: "Are you ready in life to transform all your negative experiences into positive ones? Are you ready to transform hate into love? Are you ready to transform war into peace?"
At one point during the address, the interpreter's microphone stopped working, prompting Pope Francis to use the minor mishap to illustrate his point.
"When we're not working properly (like the microphone), who do we have to turn to for help? Jesus!"
"He can tear down all the walls that lie before you."
Pope Francis stressed the importance of prayer to the young people present. In the fight against oppression, in the fight against HIV, the Pope said to ask Jesus for help, and to fight against these challenges with prayer.
In particular, he urged them to pray to Jesus and Mary, saying: "When we have a problem, the first thing we can do is go to our mother. Pray to Mary, our mother."