Jesus reminded the disciples of what he had told them before they arrived in Jerusalem, namely, that all things written in the scriptures concerning him must be fulfilled (Luke 24:44). Moreover, this pertained to how he would be mistreated and mocked by the Jewish leaders, and how he would be scourged and crucified by the gentiles, but he would rise again on the third day (cf. Luke 18:31-34; 24:25-26). He then began to open their understanding of the scriptures (Luke 24:45; cf. Acts 16:14), but this may not have been like switching on a light in order to dispel their darkness. Rather, it may have taken several appearances, before the disciples fully understood and embraced what Jesus had been telling them for some time (cf. Acts 1:3). One doesn’t rid himself of false doctrine very easily or all at once.
The scriptures reveal that the Messiah would suffer, die and rise again on the third day (Luke 24:46; cf. Genesis 3:15; 22:4; Number 21:8; 35:25; Isaiah 52:13-15; 53:1-12; Hosea 6:2; Psalm 2:1-12; 22:1-31). Up until Jesus’ resurrection, the disciples had understood that the Messiah would lead the Jewish nation against the gentile nations and defeat everyone who made war with him. The scriptures were cherry-picked by their teachers to reflect an understanding that God would enlarge the borders of the Jews and set their nation first among the nations of the world.
Paul tells us that without the crucifixion and resurrection we are yet in our sins (1Corinthians 15:17). Moreover, the scriptures say that without the shedding of blood there is no remission of sins (Hebrews 9:22). Any doctrine that makes the Messiah into a hero who cannot die (John 12:34) is simply a doctrine that can save no one. Even if, the Messiah successfully broke the power of all other nations, how would this act change the world? The hearts of men would remain untouched in a world where submission is forced through military conflict. Rather, it has always been God’s plan that man would rule over his creation (Genesis 1:28), and if mankind walked in the image of God (Genesis 1:27), he would, by virtue of his being in God’s Kingdom, be advancing the Kingdom of God as he brought God’s creation under his (man’s) control. Nevertheless, since man rebelled against God, repentance and forgiveness must be preached throughout the world in the nations of men (Acts 2:38; 3:19).
A doctrine such as the one taught the Jews in the first century AD, namely, that the Messiah never dies (John 12:34), denies the need of the Jews to repent. According to their understanding, the Messiah would simply come as a patriot to glorify the nation by defeating all her enemies. Jesus taught that repentance and forgiveness of sins must be taught **beginning** at Jerusalem (Luke 24:47; cf. Isaiah 2:3; 40:9). In other words, the Jews needed to repent and be forgiven just as much as the gentiles. There was no difference in this regard. All men sin, and all need to repent, and all need forgiveness.
Such a doctrine, whereby the Messiah simply came upon the scene as a super patriot who raised up Israel among the nations by forcing the gentiles to submit to them, would take away God’s freedom—freedom to act righteously, to judge unrighteousness etc. God is not obligated to forgive, but he does, and when he does, he does so righteously. Repentance is necessary, and the shedding of blood is necessary to bring about repentance. Therefore, to “Behold God” (Isaiah 40:9) is to behold the extent of his love for us (Zechariah 12:10-14), and beholding our God in this manner will bring healing to our hearts and cause us to repent, and Jesus told his disciples that they were witnesses to these events, namely, Jesus arrest, his crucifixion, and his resurrection (Luke 24:48), all of which needed to be preached throughout the centuries in order to get men to consider their ways, and repent and cease their rebellion against the God who loves them.