Why, according to Luke, was Jesus crucified? In responding pay attention both to the political/religious/historic reasons and to what Luke sees as God’s purposes in the death of Jesus.
To answer this question, my essay will examine the political, religious and historical background of Jesus’ life, and the repercussions of His ministry on the religious and political establishment of the time.
The historian, Luke, wanted to demonstrate that Christ’s life, death and His resurrection, were an intrinsic part of the history of Israel, the fulfilment of the covenant that God made with Abraham and his descendants:
“And I will make My covenant between Me and you, and will multiply you exceedingly.” 
(see also Genesis, Chap. 15 ; 1,2,3,4,5 and 6; Chap 17: 3,4,5,6 and 7 and Chap 22: 15,16,17 and 18). Through Abraham’s descendants the land of Israel is born and the promise of Salvation for all humanity comes through the birth of Christ. Craig Evans suggests that:
“Luke wants the reader to realize that the life of Jesus represents major events
in what scholars sometimes call Israel’s “salvation history” 
Luke gives several reasons why Jesus had to die on the Cross, which include the historic, political and religious aspect of Jesus Christ’s death, which culminated in His resurrection and the full disclosure of His divinity (see Luke’s Gospel 1:32; 24: 25, 26, 27), thus placing Jesus Christ as the promise of the Covenant that God made with Abraham:
“And beginning at Moses and all the Prophets, He expounded to them in all the Scriptures the things concerning Himself.” (Luke 1: 27)
In the Gospel of Luke we can discern that the crucifixion of Jesus was a deliberate political move by the ruling Jewish establishment - a move to remove the direct threat of Jesus to their power and authority, but Jesus was in control of His own destiny.
“Jesus sees the Cross ahead of Him as the way to win the lost…It is not a mythical “dying god” of the autumn who rises, according to the myth, in the spring, as the mystery religions teach. Jesus in the event of the crucifixion was coming against the pagan belief of false gods and religions. He was establishing Himself as the true God who loved humanity. The crucifixion was a message for all humanity, a message of love and of true redemption. On the Cross Jesus had fulfilled God’s requirement of shedding blood for the sins of humanity. On the Cross He had completed and fulfilled the promise of a saviour for Israel and the whole world.” 
He knew of His impending death, He predicted his crucifixion to Peter (see Luke 9: 20-29; 9:43)
“..These are the words which I spoke to you while I was still with you, that all things must be fulfilled which were written in the Law of Moses and the Prophets and the Psalms concerning Me” 
The Crucifixion in Luke’s Gospel points to Jesus as the true Messiah, the Son of God, who by His own volition comes back to life. Death could not hold Him. Jesus was showing Himself to be the true God who can save humanity from eternal damnation. Luke wanted to demonstrate that Christ went to the Cross because he was the Saviour of humanity. He gave His life and He took it back; which could only be achieved through God’s sovereign power He was not only a man but also a supernatural being; the God of Israel.
Jesus lived in a time of turmoil and much suffering. Israel was filled with social unrest and political upheaval. The land was filled with violence and injustice. The Jewish people, ruled at the time by the Roman Empire, were yearning for the Messiah to come and liberate them from the yoke of the Roman oppressor, to whom they must submit and pay taxes. The Jewish religious rulers did not help the people in their struggles against the burden that had been placed upon them by their enemies. The high religious Officials, the Sadducees and the Pharisees were members of the Sanhedrin. They held their posts more because of the financial and political power they received, than from a desire to serve God.
“Having arrested Him, they led Him, and brought Him into the high priest’s house” 
The Sanhedrin had little political or religious power because Israel was in the hands of the Romans. It was corrupt and did not follow God’s Law, but hankered after wealth and political power; they were subjected to Rome and Caesar, the Emperor. Pontius Pilate was sent by Caesar to reign over the Jewish people. Pilate was normally resident in the administrative capital of Caesarea (see also Acts 23:33).
“Then the whole multitude of them arose and led Him to Pilate” 
Pilate believed that, if he did not heed the outcry of the Jewish crowd against Jesus, there would be an insurgence. Although he tried to save Jesus from the hand of the Jewish rulers, in the end he acquiesced to the demands of the mob for the sake of peace and to please the religious rulers and Rome.
King Herod, resided in Galilee, but he obeyed the commands of Rome and not of God. He did not have the welfare of his Jewish subjects at heart, but wanted only to ingratiate himself both with Pilate and Rome to gain advantage for his own Kingdom. Politically he did not get on with Pilate, but after Jesus was captured and Herod had rejected Him as a fraud, Pilate and he negotiated a friendly political alliance:
“That very day Pilate and Herod became friends with each other, for previously they had been at enmity with each other (Luke 23:12)
From the beginning of His Ministry, Jesus challenged the ruling groups in Israel, especially the Pharisees. This group was committed to the oral tradition of the Mishna, to the Torah and believed they were the one group who were true to Jewish belief and ideology.
Jesus questioned their righteousness; how they perceived themselves; their belief in the Messiah and the Law. The Pharisees strenuously followed the Law and the Commandments, but with no true love for God or His people.
“Beware of the yeast of the Pharisee - beware of their hypocrisy” (Luke 12:1)
The Pharisees were very observant in the rituals of the Law.
“The Pharisees met on Friday evening (the beginning of the of the Jewish Sabbath) in small groups knows as Haburoth to eat, study the Scriptures and pray together” 
This sect believed that only God was able to forgive men for their sins, but they were not willing to recognise the Son of God when they saw Him doing deeds that only God could do, as we can see in Luke 5:17-27.
In this account, a paralytic man is lowered from the roof of a house so Jesus could heal him. Jesus not only heals him but also tells him that his sins are forgiven. He showed the Jewish rulers that He could do more than a healer was able to. He had come to save Mankind not only physically but also spiritually, to bring salvation to the soul. Jesus tells them that he has cured the man so that “they may know that the Son of Man has authority on earth to forgive sins”. Jesus, by calling Himself “the Son of Man”, was challenging the Pharisees and pronouncing His Messianic role among the Jewish Nation.
For thousands of years a main focus of Jewish belief had been the coming of the Messiah, but their perception of the Messiah and what he would accomplish differed from the actual Life and role of Jesus.
The Jewish people expected the Messiah to be a man sent by God to liberate Israel from the oppression of the Roman Empire. Israel would be a prosperous land, where peace reigned. The Messiah’s role was to bring peace to Israel; he did not have a world- wide missionary role.
Jesus, who was believed to be the Messiah by his followers, preached a message to the Nation, which could not be accepted by the Jewish rulers. He told the people to love their enemies (see Matthew 5:44) including the Romans occupiers.
The Messiah expected by the Jews would get rid of the Romans, and would not expect them to love the Roman enemy. Jesus urged the Jewish people to turn the other cheek if someone slapped them. He gave the parable of the “Good Samaritan”, showing that goodness could come from outside Israel. Jesus did not fulfil the expectation that Israel had of the Messiah.
Jesus also maintained that He was a Divine Being who was going to sit on the right side of God, in Heaven. He declared Himself to be the “Son of Man”, when He was brought before the Council of the Religious Leaders to be condemned by them (See Luke 22:67-71)
“If you are the Christ, tell us”  (verse 67)
“Hereafter the Son of Man will sit on the right hand of the power of God” (verse 69)
The Jewish rulers were furious at Jesus’ claim that He was the “Son of Man “. To claim to be the Messiah, according to Leon Morris, in the ‘Tyndale New Testament commentaries, was not a profanity. Many others had claimed the title before Jesus, but to assert that He would be sitting at the right hand of God was to be put Himself in a higher place even than the Messiah; this claim was tantamount to blasphemy as it linked Jesus to the Deity.
Jesus, with this utterance, had committed an infringement of the Law (see Deuteronomy 5:7). He was guilty of linking Himself to Deity. Jesus had broken the Law. It was the legal right of the Jewish rulers to condemn Him – they needed no more proof of guilt:
“What further testimony do we need? For we have heard it ourselves from His own mouth.” (Luke 22:71)
Jesus wounded the Pharisees’ pride, Luke (see 11:37-54; 15:2; 20:9-19). He opposed their legalistic interpretation of religion and their arrogance. The Pharisees felt affronted and embarrassed by what they perceived was Jesus’ attack on them. They began to fear Him because people were willing to listen to Him and they were losing power and authority among the Jews. Jesus was indicating that their knowledge and adherence to the Law did not make them more special in the eyes of God.
In Luke 10:30-36 Jesus relates a Parable to demonstrate that the righteous ones of God were not the Levites, or the Priests – who, like the Pharisees, were law-abiding Jews. He adopted the controversial view that righteousness was found in the Samaritan, who was considered by the Jewish people to be a sinner, not a proper Jew. In this instance the Samaritans did not follow the Law and the precepts, like the Jewish rulers, but they honoured God with their heart and their actions.
One other Jewish group that had been challenged by Jesus were the Sadducees:
“By contrast with the Pharisees, the Sadducees had their hands on the levers of political power. They were Jerusalem-based and very influential in the Council of the Jews”
Many men who were part of this sect were the leading Priests of the Temple. The Sadducees were worried about Jesus because His teaching was detrimental to the authority and status they held among the Jewish community. The Sadducees and the Pharisees belonged to the Sanhedrin Council. Both were ready to gladly accept the offer of Judas Iscariot (see chap 22 3-6) to take them to Jesus so they could arrest Him.
Judas Iscariot was a disciple of Christ, one amongst the twelve followers of Jesus who had been with Christ from the very beginning of His ministry. Judas was possessed by Satan at the time of the “The Feast of Unleavened Bread” that is the “Passover” and sided with him against Jesus (Luke 22: 3). Judas must have had an understanding of the divinity of Jesus because we read in Luke 22: 48 Jesus saying to him:
“Judas, are you betraying the Son of Man with a kiss”
It is possible that Jesus chose to reveal Himself to Judas at the time of his betrayal as the Messiah because he knew that there was a supernatural element in Judas’s betrayal. According to the words of author Joel B. Green:
“In fact, the Lukan account of Jesus’s passion and death is in part the story of unholy alliances made and unmade, as this barrier is repeatedly, if only temporarily breached. Satan and the leadership of Jerusalem are allied in their Opposition to Jesus (22.53), and it is through diabolic influence that one of the twelve, Judas, sides with the leadership against Jesus. ”
The crucifixion did not happen solely because of the Sanhedrin’s fear of Jesus being a stumbling block in their pursuit of power and richness. The Pharisees and the Sadducees were followers of the Torah. They thought they were serving God, but instead, without being consciously aware, they were serving Satan, Jesus’ enemy (Genesis 3: 15) and his purpose as Joel B Green asserts:
‘Satan and Jerusalem are allied in their opposition to Jesus’
Satan’s desire was to stop the Prophetic and Redemptive work of Jesus on the Cross. Jesus was the King of Judah; He was the Fulfilment of the Promise from God to Israel and to humanity.
In His last days Jesus fulfilled the prophecies written in the Old Testament. He came to Jerusalem on a donkey (Matthew 21; 4, 5) echoing the words of Zechariah 9: 9
“…Behold, your King is coming to you. He is just and having salvation lowly, and riding a donkey…”
and in Genesis 22: 7 Abraham prophesies the sacrifice of the Lamb:
“And Abraham said, “My son, God will provide for Himself the lamb for a burnt offering”
Jesus was the free gift to us from God, the Lamb who took away our sins. The ruling Jews and the Romans who placed Jesus on the Cross, believed that they were crucifying Jesus to enhance their own social, political and religious status. They perceived Jesus to be a human being who was a threat because of His teaching and way of life. They were not aware of the great spiritual warfare that was raging in the heavenly domain; they were doing Satan’s bidding.
“Thus it is written, and thus it was necessary for the Christ to suffer and to rise from the dead the third day, and that repentance and remission of sins should be preached in His name to all nations, beginning at Jerusalem. And you are witnesses of these things” 
Therefore to be a true disciple we need to follow Jesus. To conclude, we can say that Luke wants to show that the crucifixion of Jesus happened because He came to be the Saviour of this world, to take our sins away. Luke the historian wanted, in a scientific and systematic manner, to prove within a Jewish political, social and religious framework that Jesus Christ was the Fulfilment of God’s promise of salvation to Israel and the whole world.
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Green, Joel B, The Gospel of Luke, (Eerdmans, Cambridge, 1997)
Leaney, A R C, A commentary on the Gospel according to St Luke, (London, Adam & Charles Black. 1958,)
Marshall, I, Howard, Luke – Historian and Theologian, (Paternoster Press, Exeter, 1970, 1988 edition)
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