In 1931 a poor polish nun received a vision. Here is how she describes it in her 600-page diary:  "In the evening, when I was in my cell, I became aware of the Lord Jesus clothed in a white garment. One hand was raised in blessing, the other was touching the garment at the breast. … there came forth two large rays, one  red and the other pale. In silence I gazed intently at the Lord; ... After a while Jesus said to me, 'paint an image according to the pattern you see, with the inscription: Jesus, I trust in You.'" One hand in blessing—his mercy, his infinite outpouring love for us—the other hand at his breast—the price of that mercy to a people who refused it, his heart cut open on the cross. Jesus spoke again to this sister: "The pale ray stands for the Water which makes souls righteous; the red ray stands for the Blood which is the life of souls. These two rays issued forth from the depths of My most tender Mercy at that time when My agonizing Heart was opened by a lance on the Cross… Fortunate is the one who will dwell in their shelter." 
   In the year 2000, St. John Paul canonized this farm girl and established the Feast of Divine Mercy, always to be celebrated on the Sunday after the Glorious Resurrection.
   Mercy, God’s tender love, is the only real thing; at the end of human history, only mercy will remain. Today we hear the story of doubting Thomas, a man who refused to let go of his bitter disappointment in God’s silence at the Cross. But the Lord had returned to the apostles  as they huddled behind locked doors. “Peace be with you” are always his first words to them. Thomas was not with them, and upon returning refuses to believe in the Resurrection of Jesus. A week later, that is, today, Jesus returns to that room and turns to Thomas: Touch my wounds, and believe, my dear son. Let go of your fear. Trust me. Thomas surrenders, and so becomes a saint on the spot: “My Lord and my God.” God does exist, and is worthy of our complete trust. Paint an image, Jesus told Sr. Faustina, according to the pattern you see, with the inscription: Jesus, I trust in You. 
   But how can I trust Jesus the way Thomas did; how can I receive his mercy? I learn to trust him by obeying him. Saint John says in his first letter (1 John 5:3) that “the love of God is this, that we keep his commandments.” We know we actually love God, rather than just thinking we love him, by keeping his laws. A Christian, a disciple of Christ is one who does not simply receive God’s mercy; he gives God’s mercy. He serves as a vessel of divine mercy when he keeps his commandments. God never refuses us mercy, but we are not capable of receiving his mercy if we do not trust him enough to obey him. And so we come to the sacrament of mercy, the sacrament of confession. Confession guarantees that trustful obedience without which we are not capable of even wanting God’s mercy. We must “confess” our need for him: “my Lord and my God”, and we must confess it often.