Satan may take all the souls that God rejects, however would this be considered as beneficial? Maybe for Satan, but for the souls I think naught. Satan may take in all of these souls but he would not treat them well, and they are doomed to remain in Hell for eternity. Frankly I believe very few people end up in Hell.
It's really hard to fight with reason when it comes to faith. Faith goes beyond reason. Whatever they say, I won't believe it. I believe that God is good and God loves us all. That's my faith even if there's no proof or evidence. That's what faith is all about.
