What I found exposes OSAS for the error that it is is its proponents' understanding of what
Romans 6 through 7 teaches. If a person believes
Romans 7's description of Paul saying he could never really do the good he wanted to do applies to all believers until Jesus comes, as though we can never get victory, that person will be prey to a degree to OSAS. OSAS teaches we can never really get victory over sin. And THAT LED to the OSAS doctrine that you can sin and still be saved. It's based upon the idea no one could ever make it to heaven if there was not OSAS, because we cannot have that much victory. But
Romans 7 is not teaching every believer can never get victory over sin, but teaching that those believers who do not learn how to be led by and walk after the Spirit cannot have victory.