A collection of Common Objections to Christianity from Skeptics answered by Steve Hays. Like, for instance,
How can it be just to send people to hell when they have never had the opportunity to believe in Jesus?
No one goes to hell for disbelieving in Jesus. Disbelief is an aggravating factor. But the hellbound are already lost. Refusing the gospel isn’t what renders them damnable.
In Christian theology, nobody can be saved unless he knows and accepts the gospel. This doesn’t mean nobody can be damned unless he knows and rejects the gospel. Rather, to be lost is the default condition of sinners. To be lost is not a result of spurning the gospel. To the contrary, it’s because sinners are lost in the first place that they desperately need to be saved.
Listen to Dustin Segers and Sye Ten Bruggencate engage two atheists using presuppositional apologetics. The whole thing is 3 hours long, but you’ll get the idea if you listen to the first hour or so.