Holy Week allows us to contemplate the Passion of Christ. In the Orthros for Holy Monday, we hear the following First Kathisma:
"On the day at hand, like a lifesaving beacon, the honorable Passion breaks on the world. For Christ in His goodness presses on to His sufferings. Though He holds all creation in the hallow of His hand, yet He deigns to be suspended on the Cross to save mankind."
And the Third Kathisma reads:
"Today shines as the first-fruits of the Passion of the Lord. Come, then, all who love the feast and join together in hymns. For the Creator comes to accept the Cross, the afflictions, the beatings, and the judgment by Pilate. A servant strikes Him on the head, but He endures all things that He may save mankind. Therefore, let us cry out to Him: 'Grant remission of sins to those who venerate Your pure Passion.'"
The Sacred Hymnographers of the Church give various epithets* to describe the Passion of Christ throughout the many hymns of Holy Week.
They call it "Honorable Passion" (σεπτά πάθη - septa pathi) because the Passion of the Lord invites honor and veneration. Only hardened impious hearts are unmoved by the Passion of Christ.
They call it "Pure Passion" (άχραντα πάθη - ahranta pathi) because the body of Christ, which endured much suffering and torment, is pure and without the corruption and disease of sin. The pure and innocent body of Jesus undergoes the Passion.
They call it "Fearful Passion" (φρικτά πάθη - frikta pathi) because the Passion of Christ consisted of the most painful torture imaginable, both bodily and mentally. Knowing what He was about to endure beforehand at the hands of His own creation, voluntarily, no one can even imagine what suffering the Lord went through during the first Holy Week.
They call it "Holy Passion" (άγια πάθη - hagia pathi) because Jesus was truly the only holy person to ever suffer, as His holiness comes from Himself. "One is holy, One is Lord, Jesus Christ..." we sing at every Divine Liturgy.
They call it "Saving Passion" (σωτήρια πάθη - sotiria pathi). This particular epithet mainly applies to us and what the Passion of Christ brought us. In this sense, it also shows the ultimate purpose for why Jesus endured His Passion, which is to save mankind. Both the Passion and the Cross of Christ are the source by which the waters of salvation flow to all people through the blood of Christ, which is the medicine of our immortality through Holy Communion.
They call it "Life-Creating Passion" (ζωοποιά πάθη - zoopia pathi). This epithet foresees the goal of the Passion and Crucifixion of Christ and looks forward to the Resurrection. The Resurrection cannot take place unless the Lord endures the Crucifixion first. He died that we may live. By His death was death trampled. And for us, paradise which was once lost to us has now become paradise restored through His Passion.
The Passion of Christ is our freedom.
It was because of our sinful passions that Christ had to endure His Passion for our healing and salvation. Our passions and sins crucified the Lord of Glory. We were slaves to our passions because of the fear of death and because of him who held the power of death, the devil. Christ has trampled down death by His Passion and given us a new life where we are no longer slaves to our passions and desires, but free men and women by the grace of the Holy Spirit. He has become our Redeemer.
Why then are we still so often enslaved by our passions? Because we are sick, and the sick always suffer. This is why Christ has given the means through the Church to cure us of our passions and sins, though it is ultimately up to us if we want to take the medicine prescribed for the cure. Often we are too stubborn to take our medicine given to us by the doctor (a.k.a. spiritual father), let alone from the Physician of our souls and bodies (Jesus Christ). This is a hard saying, but it is true. And though the medicine is always within our reach, we fail to take the medicine which provides the inevitable cure.
The medicine of immortality is to organically live within the life of the Church so as to receive that which heals us in a worthy manner (though we are always unworthy) - the Body and Blood of Christ.
The Passion of the Lord is upon us and the Lord calls us all to submit to Him our passions in exchange for His forgiveness and the remission of our sins. In doing so, our purification will lead to our glorification.
* For those who do not know Greek, it should be noted that these epithets often are not translated correctly in English service books for Holy Week. Usually the translation is made to say merely "Holy Passion", ignoring the rich terminology above. This is unfortunate.