On the Second Sunday of Easter, also known as Divine Mercy Sunday, Pope Francis said that our relationship with God is a personal one, filled with his love and mercy, where we proclaim like St. Thomas: "My Lord and my God!"

"To enter into Jesus' wounds is to contemplate the boundless love flowing from his heart. It is to realize that his heart beats for me, for you, for each one of us," the pope said April 8.

"Just like in a love story, we say to God: 'You became man for me, you died and rose for me and thus you are not only God; you are my God, you are my life. In you I have found the love that I was looking for, and much more than I could ever have imagined.'"

Francis reflected on St. Thomas' exclamation in the Gospel of John during his homily for Mass for Divine Mercy Sunday in St. Peter's Square. He pointed out that it may feel strange at first to say "my Lord and my God."

But he noted how God himself said, at the beginning of the Ten Commandments: "I am the Lord your God," showing that he desires a personal relationship with each one of us, to be possessed by us, just like a jealous lover.

The Mass also marked the start of an April 8-11 meeting in Rome of some 600 Missionaries of Mercy, who were first commissioned on Ash Wednesday 2016 during the Jubilee of Mercy. Their mandate was extended by Pope Francis at the close of the holy year and the meeting is focused on spiritual formation and fellowship-building.

"As today we enter, through Christ's wounds, into the mystery of God, we come to realize that mercy is not simply one of his qualities among others, but the very beating of his heart," Francis said.

"Then, like Thomas, we no longer live as disciples, uncertain, devout but wavering. We too fall in love with the Lord! Don't be afraid of this word, in love with the Lord!"

How can we savor this love that Jesus bestows on us? How can we touch his mercy with our own hand? the pope asked. First, he said, is through the Sacrament of Confession, where we let ourselves be forgiven by God.

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Francis outlined three roadblocks we put up in our hearts about confession: shame, discouragement, and believing we are unforgivable.

"Before God we are tempted to do what the disciples did in the Gospel: to barricade ourselves behind closed doors," he said. "They did it out of fear, yet we too can be afraid, ashamed to open our hearts and confess our sins."

When we feel ashamed of our sins, this can be a gift, the pope said, because it is an invitation to our soul to let God overcome the evil in our lives, and we should not be afraid to experience shame, but instead, "pass from shame to forgiveness!"

Another struggle we might face, he said, is one of resignation or discouragement, letting ourselves think: "I've been a Christian for all this time, but nothing has changed; I keep committing the same sins."

"Then, in discouragement, we give up on mercy," he continued. "But the Lord challenges us: 'Don't you believe that my mercy is greater than your misery? Are you a backslider? Then be a backslider in asking for mercy, and we will see who comes out on top.'"

When we fall into the same sin again and again, we may experience great sorrow, but even this sorrow is beneficial, because it "slowly detaches us from sin," he said.

Thirdly, another "closed door" we may put up to keep ourselves from confession is not wanting to forgive ourselves, the pope said. Someone who has committed a grave sin may think that if they cannot, or do not want to, forgive themselves, how could God want to forgive them?

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"This door, however, is only closed on one side, our own; but for God, no door is ever completely closed," he said.

"As the Gospel tells us, he loves to enter precisely 'through closed doors,' when every entrance seems barred. There God works his wonders. He never chooses to abandon us; we are the ones who keep him out."

"Let us today, like Thomas, implore the grace to acknowledge our God: to find in his forgiveness our joy, and in his mercy our hope," he said.

Following the Mass, Pope Francis led the faithful in praying the customary Regina Coeli prayer. In his brief message before the prayer, the pope thanked all the Missionaries of Mercy gathered in Rome for their meetings.

He also wished a happy Easter to those who are members of the Orthodox Church and are thus celebrating Easter today. "May the Risen Lord fill them with light and peace, and comfort the communities that live in particularly difficult situations," he said.

Francis also denounced the use of chemical bombs, following an attack in Douma, Syria that killed over 40 men, women, and children, saying, "there is no such thing as a good war or a bad war. Nothing justifies the use of such bombs."