No one saw Jesus die on the cross. Several Bibles and passages say he did not die: 

Bible of Barnabas: "The face of Yehuda who led the soldiers to arrest Christ was transfigured into that of Christ who had been rescued by the Angels through the window to the third Heaven." 

Also the Bibles of Basilidains, Docetae, The Marcionite Gospel. 

Here brothers and sisters you have 4 chosen and recognized Bibles, also Luke 20:34-36, 24:36-41, Hebrews 5:7 and John 20:17 support Jesus was saved. 

The Bible says that Jesus did not die on the cross, that his loving creator saved Jesus from the cross as confirmed in the Koran. God loves Jesus. 

Would a compassionate, forgiving, merciful God allow his anointed Jesus to die??

* To say he was sacrificed for us, opposes the Bible's teachings (Hosea6:6) and (Matthew 9:13 and 12:7). 

* To say he died on the cross, discredits his prophethood (Deuteronomy 13:5) and (21:22-23). 

The Jews claimed they killed him to prove he was a false prophet which they still believe. The Koran is here to unite the Jews and Christians and to have them submit their will to God, to be Muslims.

Where is the information on sacrifice coming from? 

Paul, who was a Jew and his belief in Jewish sacrifice was transported into Christianity as suggested by a renowned New Testament scholar V. Taylor "The Atonement in the New Testament Teaching." Paul developed the idea by sending letters to the Corinthians, the Romans 4:25, He told the Galatians 6:4., and Ephesians 5:2, read the history yourself. Christianity is the teaching of Paul, not Jesus.

Who are we to believe??

Jesus came to confirm the Torah, not to destroy it (Matthew 23:2-3).

While Paul abolished the teachings of the Torah (Acts 13:39). 

What hour was Jesus crucified??
(Mark 15:25) It was the third hour, and they crucified him.

(John 19:14) It was the sixth hour, and he was not yet crucified

Who bore the cross??

(Matthew 27:32) The compelled Simon to bear the cross of Jesus./ also(Luke 23:26)& (Mark 15:21).

(John 19:17) Jesus was bearing his cross himself.

What did they put Jesus on??

(Mark 15:21) They put Jesus on the cross.

(Peter 2:24) They put Jesus on the tree./ also (Gal3:13)

What did they give Jesus to drink??

(Mark 15:23) They gave him wine mingled with myrrh to drink.

(Matthew 27:34) Thew gave him vinegar mingled with gall to drink.

What happened to Judas??

(Mat 27:5) Judas went and hanged himself.

(Acts 1:18) Judas fell headlong, and burst asunder in the midst, and all his bowels gushed out.

Many earlier sects of Christians believed that it was Judas who died in the place of Jesus, with the contradictions at hand, maybe those earlier Christians were right.

Who went to the grave of Jesus??

(John 20:1) Early on the first day of the week, while it was still dark, Mary Magdalene went to the tomb and saw that the stone had been removed from the entrance.

(Mat 28:1) Mary Mag-da-le-ne and another Mary.

(Luke 24:10) Mary Mag-da-le-ne and another Mary and Jo'an-na and some other women.

(Mark 16:1) Mary Mag-da-le-ne and another Mary and Sa-lo'-me.

Angel??

(John 20:12) One woman saw two angels at the grave of Jesus.

(Mat 28:2) Two women saw one angel.

(Luke 24:3) Three women saw two men.

(Mark 16:5) Three women saw one man.

Who was told??

(Luke 24:9) Mary the Mag-da-le and Mary the Mother of James and Jo'an-na returned back from the grave and told the eleven apostles all of what they saw.

(Mark 16:8) Mary the Mag-da-le and Mary and Sa-lo'-me returned back from the grave, and did not tell anyone anything because  they were afraid.

During the time of the assumed crucifixion, as you see, was a time of confusion, because no one saw Jesus die. (Matthew 26:56) 

But this has all taken place that the writings of the prophets might  fulfilled." Then all the disciples deserted him and fled."

So the Qur'an says: 4:157 
"That they said (in boast), "We killed Christ Jesus the son of Mary, the Messenger of Allah"- but they killed him not, nor crucified him, but so it was made to appear to them, and those who differ therein are full of doubts, with no (certain) knowledge, butonly conjecture to follow, for of a surety they killed him not:"

When Abraham was told by God to sacrifice his son, his son did not object or question him, if Jesus was sent to be sacrificed for our sins, why would he question God? 

(Matthew 27:46): ".. . My God, my God, why hast thou forsaken me?" 

Could this not come from someone other than Jesus? Even a Non Prophet would smile at agony as he knew that his death would win him the title of martyr. 

Was this not an insult to Jesus in not having faith in Allah?

The sacrifice that has to be made to be forgiven for our sins is the sacrifice of our will to the Creator Allah, as confirmed in the Bible. 

Not only do we rely on faith, but also action and reality all combined. We believe in the same God, you have been taught by the recipients of your hard earned 10% of your income tithing that the Koran is not the word of God, that is sad, because then you would learn as every chapter begins "God is the Most Gracious, the Most Merciful." 

In Islam, only 3% of your income goes straight to the poor, such as a relative. None is required to go the Church or Mosque. 3% of the wheat in the world would feed all the starving.