Otherwise, Christ would have had to suffer repeatedly since the foundation of the world. But now He has appeared once for all at the end of the ages to do away with sin by the sacrifice of Himself.
KJV
For then must he often have suffered since the foundation of the world: but now once in the end of the world hath he appeared to put away sin by the sacrifice of himself.
ASV
else must he often have suffered since the foundation of the world: but now once at the end of the ages hath he been manifested to put away sin by the sacrifice of himself.