Traditionally, Christians "celebrate" the Crucifixion of Jesus on a Friday, and His Resurrection on the following Sunday. Without spending time on the debate over which day of the week He served as "our Passover" (1 Cor. 5:7), let me address the adjective "good" with regard to the horrific death of the Creator of the Universe (Jn. 1:1-3; Col. 1:16; Heb. 1:1-2).
By calling the event "good," we are declaring to the whole world that we are totally selfish human beings! We are making the death of the Son of God, all about us! Of course, to those of us who believe, His death, in paying the penalty for our sin so that we might have eternal life, is far more than just a "good" thing. However, it was the ultimate horror for the Father and for Jesus! And, I doubt very seriously that when those who have rejected the Lord are standing before Him on Judgment Day, and they recognize their role in putting Jesus to death, that they will see it as being a "good" thing! Also, I am absolutely certain that Satan and his minions thought it was a "good" day until they realized He had risen to conquer sin, hell, and death!
In the New Testament Gospels, there are seven recorded statements made by Jesus during His Crucifixion. Three of them appear only in Luke, and three only in John. The other saying is in both Matthew and Mark. The traditional order for the sayings is as follows:
1. "Father, forgive them, for they know not what they do" (Lk. 23:34).
2. "Verily I say unto thee, today shalt thou be with Me in paradise" (Lk. 23:43).
3. "Woman, behold thy Son!" and to John, "... behold thy mother" (Jn. 19:26-27).
4. "My God, My God, why hast Thou forsaken Me?" (Matt. 27:46; Mk. 15:34).
5. "I thirst" (Jn. 19:28).
6. "It is finished" (Jn. 19:30).
7. "Father, into Thy hands I commend My spirit (Lk. 23:46).
Some have called these seven sayings, words of: 1. Forgiveness; 2. Salvation; 3. Relationship; 4. Abandonment; 5. Distress; 6. Triumph; 7. Reunion.
"Celebrating" Good Friday sort of reminds me of the hymn "The Old Rugged Cross." While born-again believers are thankful that Jesus was willing to suffer such agony on our behalf, I doubt that He "loves that old wooden cross!" I really find it disgusting that we sing about the instrument which put our Savior to death, as though it is something to be cherished. Can you imagine someone taking the weapon which was used to murder his mother, and mounting it on the wall? I hate that cross, and I hate the fact that because of my sin, I am partly responsible for my Lord's suffering! But I thank God for allowing it to happen so that I can spend eternity praising Him!