Why is that not possible for those in Christ?Not possible for those who are in Christ.
Satan and his angels will be destroyed to exist no more. Meanwhile, the book of Job tells us that God spoke with Satan. Satan serves God's purpose. I'd suggest you don't over think it with your own doctrine. Especially with regard to the spiritual status of Christians who answer hypothetical's regarding dentists and Satan having teeth.
Second question, just because God ALLOWED Satan to do something doesn't mean that Satan serves God's purpose. God doesn't condone sin, hatred, ect.
Upvote
0