An atheist writes:

The reasoning you present here could be used to defend an evil God.
So, if I say “God is evil”, I could point out at all the bad things that happen in the World.
You could then say that in the World there are actually a lot of good things happening, too.
At this point, using your very argument, I could reply that God works in mysterious ways, he deceives us, but his ultimate goal is always our suffering and misery.

Assuming that God exists, can you make a case for Him being good that cannot also be used for Him to being evil?
Mind you, if you just add another unproved assumption, such as “I have Faith that God is good”, you allow anyone to state “I have faith that God is evil” and act according to such horrible belief.

This is quite a practical problem, because “I have faith that God is evil” is not too far from “I have faith that God is good” provided that “good” means “wants me to kill the unbelievers”.

What if God gave us the Bible to test our rationality and skeptical thinking, and will reward only those that do NOT BELIEVE in Him?
Can you exclude this, or prove that it is less probable than Him sending to Heaven only the believers?
He works in mysterious ways, after all.

See also this post.

The comment boils down to two important questions. The first one is, How do I know that God is good? The second one is, How do I know that what he presented in the Bible is true? Because the second question has been asked, I will have difficulties in using Scripture to answer the questions. I must instead turn to natural theology.

Before I do that, I think that it is really important to mention that Scripture confirms all throughout that God is good, and that his promises are trustworthy. The problem that our atheist friend wants me to address, however, rejects the authority of Scripture outright. Therefore, I cannot simply point to Scripture and say, “Look at verses like Psalm 100:5, 34:8; Nahum 1:7; 2 Peter 1:3; or Matthew 19:17!”

The Bible is the Word of God (2 Tim 3:16-17), and God cannot lie (Titus 1:2). It is therefore reasonable to conclude that the promises of Scripture are true. According to Scripture, God is good and his promises are trustworthy.

But what do I say to someone who rejects the authority of Scripture? Obviously, quoting Scripture won’t work. Instead, we look to natural theology to prove that God is good. After we look at that, we can then move into using fulfilled prophecy to prove that Scripture is trustworthy. Finally, we can arrive at a conclusion from Scripture that God is good and his promises are trustworthy.

But is all of that necessary? See, I’m dealing with an atheist. I can only assume a postmodern, naturalistic worldview. Postmodern viewpoint assumes that all truth is relative and that there is no such thing as an absolute truth. Naturalism precludes the possibility of miraculous fulfillment of prophecy. So already, because of my respondent’s worldview, I’m starting the count at 0-2.

Scripture claims absolute truth, which assaults the sensibilities of the postmodern mind. In the mind of the naturalist, fulfillment of prophecy is a coincidence rather than a miracle. Miracles are simply not yet explained by science; so attributing them to God is fallacious in the mind of the postmodern naturalist.

My best weapons are moot to the mind of the postmodern naturalist, and I can do nothing to alter my respondent’s worldview by clever argumentation. Therefore, my entire response to his question will be an exercise in futility. So unless I hear that my commenter is sincerely willing to learn something about theistic views, I will leave this essay for another time. Perhaps it will never get written.