Speaking as someone who taught Sunday school for 12 years and also served as a deacon body leader for 7 years, I respectfully disagree with you.....
No where in the Bible are we told that we can make any sort of judgments about others. In fact, the Bible gives some very specific reasons not to be judgmental. (See Matthew 7)
And while the Bible does name some sins specifically, it also states that all sins are the same in the eyes of God....this means that if I happen to have an affair, it is no different than someone else stealing food to God's way of seeing things.
At no point does Jesus tell us that we are to haughilty flaunt our beliefs at others, nor are we to comdemn them for believing differently.
We are told to love one another....Jesus even says that this is greatest commandment of all.....simply to love one another.
Judgement of who will or who won't be saved is God''s business, and His alone.
Yes, Jesus did say to spread the gospel throughout the world.....but at no time did he say to condemn anyone else while doing so.