Q
What does the Bible say about Cremation (if anything)? I know it says “The graves will be opened and the dead in Christ shall rise!”
A
The Bible is silent on cremation. But consider this. When a dead body is buried it soon decays and turns to dust (Genesis 3:19). When Paul said the dead in Christ will rise first, he meant at the rapture / resurrection the spirits of dead believers will be given new resurrection bodies that will make it appear as if they’ve risen from their graves. This will happen just before living believers will be changed from mortal to immortal. Then we’ll all go together to our heavenly dwelling.
Therefore whether a dead body is cremated or not does not matter.