"Who would believe what we have heard?" (Isaiah 53:1)
Behold the cross. Look at what we did. Just look at what we did to Mary's boy. His only crime was loving us, having faith in us, forgiving us, healing us, and this is how we repay him. This is what we do to the greatest gift our Father in heaven has ever given to us. Look at what we did to our God.
The cross is a challenge to each of us. As Max Lucado says, we cannot ignore the cross nor be indifferent to it. When we behold the power of Christ's love for us as he hung there in agony, we must ask ourselves: "What can I do, what MUST I do to repay such love?" Everyone around that cross reacted in different ways to what transpired on Golgotha. They may have reacted with scorn or with love but none of the participants in this drama were indifferent. The thing is that we take the cross for granted. We want our Jesus clean and risen and glorious and smiling, but how do we react when he is being tortured on a piece of wood, gasping painfully for every breath, looking almost inhuman: "so marred were his features, beyond that of mortals his appearance, beyond that of human beings (Isaiah 52:14)."
As we come forward to adore the Holy Cross, take in what he did for you. He did this, he gave his life, he suffered the cruelest of deaths because he loved you. It was Blessed John Paul II that once said during a Stations of the Cross: "Look at what you have done, in this man, to your God."