We are told that if you do something wrong the consequences are bad, Hell. We therefore live in fear. 
If we do something good then nice things happen we go to heaven. We are happy with this. 
The biggest sinner in this world we are told is Satan the devil. Now should we ‘pray’ for this soul, as everyone had a chance of redemption. The problem is if the devil repents his sins and gets to heaven there is no more Hell. Nothing left to be frightene