In 1 Corinthians 15:12-14, it says
The Resurrection of the Dead12But if it is preached that Christ has been raised from the dead, how can some of you say that there is no resurrection of the dead? 13If there is no resurrection of the dead, then not even Christ has been raised. 14And if Christ has not been raised, our preaching is useless and so is your faith.
So, why is our faith useless if there is no resurrection of the dead? Well first of all, let's look at Isaiah 53: 2-5, which describes Jesus.
2 He grew up before him like a tender shoot,
and like a root out of dry ground.
He had no beauty or majesty to attract us to him,
nothing in his appearance that we should desire him.
3 He was despised and rejected by men,
a man of sorrows, and familiar with suffering.
Like one from whom men hide their faces
he was despised, and we esteemed him not.
4 Surely he took up our infirmities
and carried our sorrows,
yet we considered him stricken by God,
smitten by him, and afflicted.
5 But he was pierced for our transgressions,
he was crushed for our iniquities;
the punishment that brought us peace was upon him,
and by his wounds we are healed.
First of all, it's interesting to note that he was not physically beautiful like most paintings portray him to be. People couldn't bear to look at him. He was a man of sorrows and familiar with suffering.
But more to the purposes of this discussion is that he was pierced and crushed for our sins. Actually, if you read the different accounts of the crucifixion in the four gospels, you see that he was betrayed (sold), abandoned by everyone, falsely accused, denied by his best friend, on trial before his people, on trial before the government, flogged (39 lashings with a whip made of nine leather cords with sharp objects tied into it - a punishment meant to torture as much as possible without actually killing the person), mocked, spat upon, beaten on the head again and again while wearing a crown of thorns, made to carry his cross, to which he was finally nailed, had his few belongings divided up in front of him, his divinity attacked ("come down from the cross now if you really are the Son of God," and to borrow a quote, was ever such evil belched from the mouth of hell?). And finally to die.
Satan was trying very hard until the last minute to get him either to give up, or to sin. If he sinned, then he would have had to die for his own sins. But he held fast, remained without sin, and died for ours.
So why did he need to be resurrected? I mean, our punishment was already paid for in his death. God's law required a sacrifice of blood for sins, thus the jewish custom of sacrificing animals.
22In fact, the law requires that nearly everything be cleansed with blood, and without the shedding of blood there is no forgiveness.
The sacrifice was made, and we are forgiven. So again, why did he need to be resurrected? Sure, it's faith-building. Sure, he sets the path for us to follow so we can all be resurrected and spend eternity with God. But why is our faith useless if he were not resurrected?
25He was delivered over to death for our sins and was raised to life for our justification.
What does it mean to be justified? Well, when we justify ourselves we try to clear our name. It means to be cleared "just as if I had not sinned."
You know, in Revelations 12:10 it says,
10Then I heard a loud voice in heaven say:
"Now have come the salvation and the power and the kingdom of our God,
and the authority of his Christ.
For the accuser of our brothers,
who accuses them before our God day and night,
has been hurled down.
So Satan accuses us day and night (ever feel like that?). And in heaven (before Satan gets crushed under our feet) he's going to stand next to us before God and accuse us of all our sins. And we will say, "Yes, but Jesus died for those sins." Then Satan will say, "But you killed the Son of God. You killed Jesus." And we will say, "What are you talking about? He's right there. He's not dead!"
So we not only needed Jesus to die for us in order to be forgiven of our sins, we needed him to be resurrected for us to be cleared of our guilt for his death.