When laying this series out I seem to have forgotten to begin with this section, but better late than never. I should have started this post by making it clear that evil and suffering are not something we use to prove God's existence, but rather what the atheist will try to use to dismiss it. Unlike proving the resurrection we don't have the burden of proof here. It's up to the atheist to use evil and suffering to prove God doesn't exist, and believe me they will try. Too often believers allow non-believers to pass that burden, but not this time.
The conversation often unfolds in a statement like "tell me why your God permits suffering if he's loving." Then they sit back and play the role of skeptic while you explain something they have no intention of trying to absorb. While this is a great strategy on the part of the atheist, it's a philosophically illegitimate and intellectually dishonest way to debate. Don't allow them to dodge their mental responsibility here. They are saying that an omnipotent, loving God and the concept of suffering can't coexist so make them prove it. Demand premises and support for their argument. Then it's your turn to sit back and play the skeptic. Chances are they don't have any support, just an emotionally driven "feeling" that God wouldn't allow suffering. This is why the chart I've listed below (and in the previous post) doesn't go any further on the emotional problem of suffering. If you're engaged in an argument based on emotions then asking someone to really prove their point doesn't proceed beyond their feelings. Feelings won't have premises or support.
Play Calling:
Before you get too deep into the argument you need to find out which version of it you're about to participate in so you're in the right formation. I'd go with a question like "are you saying that it's impossible for God and the suffering in the world to coexist, or are you suggesting that it's merely improbable?" For starters, most atheist aren't expecting you to be prepared for an actual debate. This person has probably used their little attack several times in the past with no one around to properly call them out on it. They're expecting to ruffle your feathers a bit, and at best, they expect you to give them a Bible verse. If they're like most atheists then they've never really thought about what they blurted out. Be gracious and help them clarify what they believe if necessary. Their explanation of what they believe will determine which version of the argument you're about to be in. While you want to show them the fallacy in their argument, you still want to do so with care. There's a good chance they're using suffering and evil as an assault on God because they've suffered themselves. Make sure you don't just see them as an opponent, but rather an opponent with a soul.
Going Forward:
Again, I'm sorry for the confusion. This really should have been my first post in the series, but I needed to get it in so it's right in the middle instead. I hope you can see how important it is to get this right. There isn't a day that goes by where evil and suffering aren't on full display in a fallen world. On a daily basis we see death, natural disasters and heinous evil everywhere. It presents an unlimited number of opportunities for an atheist to evangelize. For the rest of the series I will go deeper into the two different versions of the intellectual problem of suffering. Once you make someone realize that an emotional argument won't hold water then they have to get off the field or call an audible and get into the intellectual argument. From there your questions will help you determine if you need to go with the logical version or the evidential version.
The one thing that all of the topics I've covered to this point have in common is that none of them have the ability to save people. God and God alone saves people, but that doesn't negate our responsibility as believers to defend our faith. If we're going to defend it, I see no problem in doing it well and having a game plan. Not only is evil and suffering a point of debate between atheists and believers, but if you're a parent then it's something you'll have to explain to your children. While I wouldn't suggest that you demand a set of premises from your kids when the topic comes up, I still feel like this will help you explain why suffering happens so it doesn't become a stumbling block.