I read in a bulletin article about thirty years ago about an interesting grave in Hanover, Germany. It was the grave of a woman who, for her entire life, did not believe in the resurrection.
In her will she directed there be put huge slabs of concrete over her grave fastened to the ground by steel clasps. She said before she died, "I don't believe in the resurrection. But if there is a resurrection, I'm not going to go, I'm staying in the grave. And on the tombstone she had these words written, "This grave is to never be opened."
Guess what? Beneath those stones was a little seed. It began to grow. And that little seed formed a plant, which pushed up those stones from the ground. And somehow the plant that grew from the seed began to push those slabs and so disjointed them that the clasps became undone. The slabs were pushed aside, all because of that little seed.
The moral in that story was that some day, God will only have to speak one word, “Arise!” No matter who died in unbelief, they will not have spared themselves the day of resurrection and judgment. All will rise to face God.