Make opponents live up to their own book of rules. You can kill them with this, for they can no more obey their own rules than the Christian church can live up to Christianity.
A Christian rejects this knowing "all have sinned and fall short of the glory of God." A reasonable person would reject this knowing something of human nature but we're not dealing with reasonable people.
There aren’t a lot of hardcore leftists. They’re the ones that are unreasonable.
You hit that on the head.
“THE NEXT TIME YOU THINK YOU ARE PERFECT...TRY WALKING ON WATER”