The questioner also says:
There is already eternal life (Daniel 12) in Old Testament. Then what is the need for our Lord Jesus to die on cross and raise on 3rd day only to promise us eternal life again?
Eternal life promised as a result of Jesus’ death, is the same for those who came before Jesus and for those who came after Jesus. Jesus’ sacrifice was retrospective, as verified by the following passages:
Hebrews 9:25-28:
Nor was it to offer himself repeatedly, as the high priest enters the holy places every year with blood not his own, for then he would have had to suffer repeatedly since the foundation of the world. But as it is, he has appeared once for all at the end of the ages to put away sin by the sacrifice of himself. And just as it is appointed for man to die once, and after that comes judgment, so Christ, having been offered once to bear the sins of many, will appear a second time, not to deal with sin but to save those who are eagerly waiting for him.
We see here that the type or copy as portrayed by the high priest, was inferior to the true thing (Jesus). The high priest had to repeatedly enter the holy place with the blood of the sacrifices. Jesus only had to sacrifice himself once for people from all ages – they looked forward – we look back.
And again, Hebrews 10:10-14:
And by that will we have been sanctified through the offering of the body of Jesus Christ once for all. And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God, waiting from that time until his enemies should be made a footstool for his feet. For by a single offering he has perfected for all time those who are being sanctified.
There was a need for our Lord Jesus to die for us to gain eternal life, because this was how God decreed salvation would occur. Those who lived before Jesus, were sanctified by his sacrifice and their faith in what they knew of it, just as we are. Just as we have to:
- look to the Messiah
- have faith
- die to serving sin and live to serving God (See Romans 6)
to live, so did they. They didn’t have the clear picture of Jesus that we have, but they had the types of Christ presented in great detail through the Old Testament; they also had the teaching and witness of the prophets, priests and judges.
Some examples of the types of Christ to help people in ancient times:
- the animal slain in Gen 3:21
- Melchizedek Gen 14:18
- the life of Joseph
- the Passover lamb Ex 12:5 cf 1 Cor 5:10
- the serpent on the pole Num 21:8
- Jonah Matt 12:40
and many others.
Abraham is a helpful example to explain this concept. Jesus said in John 8:56:
Your father Abraham rejoiced that he would see my day. He saw it and was glad.
How did Abraham see Jesus’ day, when he died approximately 2000 years before Jesus birth? I think there are several ways Abraham saw Jesus day. If we look at one of the amazing promises God made to Abraham in Genesis 22:16-18, we get a bit of an insight:
“By myself I have sworn, declares the LORD, because you have done this and have not withheld your son, your only son, I will surely bless you, and I will surely multiply your offspring as the stars of heaven and as the sand that is on the seashore. And your offspring shall possess the gate of his enemies, and in your offspring shall all the nations of the earth be blessed, because you have obeyed my voice.”
God is telling Abraham that a very special descendant of his would come and through him, people from all nations would be blessed and that he would possess the gate of his enemies – or rule his enemies. This is a prophecy of Jesus – Abraham saw the coming of this great descendent through faith, and rejoiced. As Hebrews 11:12-13 describes:
Therefore from one man, and him as good as dead, were born descendants as many as the stars of heaven and as many as the innumerable grains of sand by the seashore. These [the faithful] all died in faith, not having received the things promised, but having seen them and greeted them from afar, and having acknowledged that they were strangers and exiles on the earth.
Abraham saw the promises. He saw from afar the outworking of the promises and rejoiced in them. So, like the others mentioned in Hebrews 11, he was saved by his faith in God’s provision and his faithful life in God’s service. In essence – the same then and now.