In our own stubborn pride, though, we very often refuse to submit to the will of Christ, thinking that we somehow know better than he, or that Jesus wants to take something away from us.
Simply consider the situation of our first parents. There in Paradise they refused to let themselves be ruled by God; they rebelled against the Lord in an effort to be free and thus found themselves bound fast by the chains of sin and death. The tree of the knowledge of good and evil, the tree of life, became for them the tree of death. Consequent of their rebellion they were cast out of Paradise, out of the Kingdom of God.
We know that we cannot enter Paradise on our own, for the Lord has placed there “the cherubim and the fiery revolving sword, to guard the way to the tree of life” (Genesis 3:24). Why did the Lord close the gates of paradise to us? He did so because “the hands that Adam stretched out toward the tree of knowledge, breaking the commandment, were unworthy of stretching out toward the tree of life to receive the gifts of the God that they had despised.” 
Even so, the Lord’s love for sinful humanity never ceased or lessened, leading him to call Noah, Abraham, Moses and countless others - David among them - to prepare mankind for the day of salvation, for the day of true freedom when man and woman would again be ushered into Paradise, when those gates would be opened and the fiery sword cause us no harm. How are those gates, that Christ himself has closed, to be opened? They are opened by the power of the cross, for the cross is the key to paradise.
When the Son of God took on our flesh he came among us as the second Adam. “Our Lord took these hands and attached them to the cross, so that they might kill their killer and arrive at his marvelous life.” This is why today we celebrate the Solemnity of our Lord Jesus Christ the King. It was on the cross that
…the blood of a spotless lamb dissolved the pact of that ancient transgression. There the whole perversity of the devil’s mastery was abolished, while humility triumphed as conqueror over boasting pride… Who could explain the mystery of such a great gift? Who could describe the power of such a marvelous transformation? In a brief moment of time, the guilt of a longstanding wickedness was abolished.It is on the Cross that the true power of Christ is revealed, clothed in his humility.
In today’s Gospel we are met with two thieves: one who mocks Christ and refuses to submit to him, and another who submits to the will of Christ and takes his gentle yoke upon his shoulders (see Matthew 11:29).
“Today you will be with me in Paradise,” says the Lord Jesus as he hangs on the Cross (Luke 12:43). What beautiful and comforting words he speaks to the repentant thief, whom tradition names Dismas.
We see in Dismas the example of true Christian faith. Simply consider what this thief saw:
His faith in the kingdom did not depend on seeing Christ. He did not see him in his radiant glory or behold him looking down from heaven. He did not see the angels serving him. To put it plainly, he certainly did not see Christ walking about in freedom, but on a gibbet, drinking vinegar and crowned with thorns. He saw him fastened to the cross and heard him begging for help, “My God, my God, why have you forsaken me” (Psalm 22:1)?It was precisely in seeing Christ crucified that Dismas’ faith awakened and he beheld true love and salvation. It was here that the repentant thief recognized the Kingship of Christ, leading him to beg, “Jesus, remember when you come into your kingdom” (Luke 23:42). Looking upon the cross, Dismas came to know the Lord so intimately that he learned to call him whom he had not known by name.
The cross that led Dismas to faith led the first thief to mockery. Reviling Jesus, he said, “Are you not the Messiah? Save yourself and us” (Luke 23:39). Whereas Dismas was moved with compassion for this innocent sufferer, the other thief thought only of himself. Remaining in his stubborn pride, he refused to yield to the power of love. He closed his eyes to the beauty that hung on the cross next to him. He would not allow himself to be conquered by this King.
So many people today have this same blindness: they refuse to see the beautiful love of Christ, though manifestations of it surround them each day. Paradise, once blocked off from us because of our sin, now lies open to those who extend their hands in humble love and faithful service to Christ.
With the Cross, Jesus opens wide the door of God, the door between God and men. Now it is open. But also from the other side the Lord knocks with his Cross: He knocks at the door of the world, at the doors of our hearts, which so often and in such great numbers are closed to God. And he speaks to us more or less in this way: If the proofs that God gives of himself in creation do not succeed in opening you to him; if the word of Scripture and the message of the Church leave you indifferent - then look at me, your Lord and your God.Today, Christ the King knocks with his Cross at the door our hearts, asking us to prepare them for his throne. Will you let the Crucified King reign over your life? Do not fear his power, for it is the power of love, before which no other power can stand.
The tree brought ruin to Adam. It will bring you into paradise. Do not fear the Serpent. He will not throw you out, for he has fallen from heaven. [Jesus will] not say to you, “This day you will depart,” but “This day you will be with me.” Take heart; you will not be thrown out. Do not fear the flaming sword, because it stands in awe of its Lord. Ephrem the Syrian, Commentary on Tatian’s Diatessaron, 20.24 in Ancient Christian Commentary on Scripture, New Testament, Vol. III: Luke. Arthur A. Just, ed. (Downer’s Grove, Illinois: Inter Varsity Press, 2003), 365.
 Saint Leo the Great, Sermon 55.3, in Ibid., 366.
 Saint Jerome, On Lazarus and Dives, in Ibid., 366-367.
 Pope Benedict XVI, Homily, 1 April 2007.
 Cyril of Jerusalem, Catechetical Lectures, 13.31 in Ancient Christian Commentary on Scriptures, New Testament Vol. III, 366.