Yes, simply said and true. However, atonement was an OT revelation, preparing for the New Covenant. The OT saints had a covering by the blood sacrifices (looking ahead to Jesus as the Lamb of God, even if they did fully understand this). They, like us, were saved by their faith. But OT saints were not called (as we are in this age) to be part of the Bride of Christ... Christ in us, and we in Christ. We are so blessed.
None of the people of the Lord God, including the OT saints, were saved from the descent after they die, but they were saved for not descenting in the same place as the people of the rest of the world.
They had been given their own place in the Land of the dead.
There, they were waiting for God's Christ to come and take them out from there.
Abraham had this revelation before he died, (jesus said; Abraham had seen my day and he rejoice ),
I am not saying that all the children of the Lord had this knowledge, that did not really mater, because when they gather to Abraham , he would informed them.
David was one who knew, for he said my Lord God is the Christ to be, I will descent to Seol when I die, but he won't leave me there forever .
That's where Abraham received his Descendans and he show that indeed the Lord had bless him, and he made him a Greate Nation.
As the people were descending to Abraham's BOSSOM they informed him about everything.
That was the first stop of Jesus after his death on the Cross.
Jonh the Baptis who announce the coming of Christ here on earth, he also had the mission to anouncing his coming to Abraham and to all the others who were in the Bossom of Abraham, the paradise of the children of the Lord God,
(today you will be with me in paradise),
while they were waiting for him as the Christ to take them to Heaven with him at the time of his resuraction.
Jesus died for all And he preach the Gospel to all who had died before him, unto the first man who die and was taken captive by the Devil,
ABEL, and the first man ADAM.
God Raised Jesus from the dead and gave him the Heavens as his inheritance.
That's where Jesus took everyone who believed in him, when he preach the Gospel to those who had die before him.
When God raised him from the dead , they were raised up together with him, God's children in the name of Jesus Christ.
Jesus said; I will descent to the very low parts of the earth and show my self to all the powers and fallen angels down their, before I ascent to the very high,
Every one must seem me and bow down to me, I hope that no one expects the fallen angels to go to Heaven to bow down to him, that's why Jesus had to go to their place of prison to show himself to them.
Not only the OT saints , but everyone who had die before him and believe in him, down in Seol, Jesus took out from their in the new Promish Land, the Heavenly one.
Hope that no one expects those who had die before Jesus to be in their body when they head the Gospel from Jesus and believed.
They were saved by faith only, the way we are saved ourselfs.
That's the mission of Jesus those three days, everyone must here the Gospel, and the dead heard it from Jesus and believed, and were saved first, before the living.
Jesus said; the dead will hear his voice and raised up first. The dead will raise first.