Well, WE do. It would be nice if you'd consider that some people who aren't as stupid as you like to think we are do think we know this, because maybe it might cause you to stop and think it's possible for this to be true, but if not, then not.
But it's not knowledge, it's opinion. You know, like a Muslim's opinion that the Koran is God's word.
No it's not, it is something we KNOW, and the Bible and the God of the Bible are the ONLY things that are known in this way. This is one of those things I'd ask you to CONSIDER you might be wrong about. It's like this:
Hbr 11:1 Now faith is ... the evidence of things not seen.
That SOUNDS so reasonable ...
'Cos it is. If God's omnipotent, he can intervene in anything. He chooses not to.
This simply denies His whole revelation about How He operates and how reality is structured. You want Him to violate His own laws. Theoretically, as I said, He COULD have set things up entirely differently, even in such a way that would require Him to intervene, but He didn't, He set them up the way He set them up, and again, He could only do the most just and righteous thing so that's how He set things up whether we can grasp any of it with our fallen minds or not.
And again, I think this is all about His leaving human beings made in His image free to make a nearly perfect mess of things on our own. The way to prevent evil is to follow His laws and to make laws for nations that follow His laws, but you all violate His laws and are supporting laws more and more that violate His laws. We can also pray for His righteousness to prevail, but you all work against His righteousness. I'll agree that the church isn't on top of these things as we should be either, too many of us get drawn away into the kind of thinking on EvC forum instead of following God. I guess that makes you happy but that's one explanation for why the evil you decry occurs as it does and in fact is growing worse every day.
You may think that that's a good idea, but good or bad it is (supposing he exists) what he does.
I don't judge God. You want Him to eradicate sin -- certain kinds of sin anyway since I'm sure you're very fond of your own sins -- or to have prevented it in the first place, but if He did that we would no longer have free will, we'd be automatons.
Fear not, all sin will be judged in the end. By the God you despise so much because He doesn't obey you but requires that you obey Him instead. Again, I simply humbly suggest CONSIDER that God's way of doing things is better than anything you could dream up, and that, maybe, really, the existence of such evils is really partly your own fault since you DO like your sins, you just don't like others' and you think God's law should allow yours and others you decree to be morally acceptable by your standards.
Despite being allegedly unalterably opposed to sin, he lets it "play out", as you say. Unless the sin involves children being cheeky to a bald guy, then he kills them.
As jaywill pointed out those were not children they were young men, probably something like an inner city gang, and they were taunting a servant of God, therefore taunting God.
Oh God is certainly unalterably opposed to sin, and has promised that it will all be punished to exact perfection in the end, as Jesus also affirmed when He said He came not to abolish the Law but to fulfill it, down to every jot and tittle or comma and period. You, however, despise His Law, so does the rapist-murderer. If God intervened to stop the rapist-murdered He'd also intervene to stop your long list of everyday sins as well. And some of yours have committed a form of rape and murder too, if you understand the sermon on the mount.
Theoretically God COULD have made the whole thing some other way completely but why should I trust my own ideas about what He could or should have done?
Well, that's what you're doing, isn't it? In the end, you do all your thinking with your own brain.
I don't have any more natural liking for God's laws against my sins than you do, I had a big struggle with a lot of His decrees at first; I don't have any more natural understanding of why He does what He does than you do. The difference is that I am willing to give up my opinions and submit to His revelation because I believe it IS His revelation. That is NOT at all imposing my own thinking on Him the way you impose yours on Him. You are simply FOLLOWING where your brain leads you, I've had to learn to STOP following where my brain leads me and learn a whole new way of thinking. That's called REPENTANCE, which I think also describes what I keep recommending about stopping and considering you might be wrong in where your brain leads you. The rewards have been well worth it, to put it mildly, but the method is NOT how you are characterizing it.
I for one believe that what He says in His word is true, that He is good, that the way things are is the only way they could be for the best possible outcome. He is good and I am not in a position to see why He did what He did as He did it, I have to take it on faith.
But don't you see that you could say that about anyone or anything? You could be worshiping the absolute quintessence of evil and have faith that despite all appearances it's really good.
Of course if that's what you think I'm advocating I can't blame you for refusing to consider anything I say. I rather think that can't possibly be what you get out of what I say, but if it is, it is, that's your choice in the end.
I obviously can't talk you out of your moral judgment, that's why I didn't try.
That's not a moral judgement, those are just facts.
Fact 1: God does not intervene in many horror. He didn't smite Stalin or Pol Pot, for example, to name two people who died natural deaths after committing massive genocides.
But where on earth are you getting the idea that's how God should operate? He's never said He operates that way, you are just making it up and imposing it on Him.
Fact 2: The Bible portrays him as being perfectly willing to intervene in certain cases. Blammo, a pestilence, ka-zap, people drop dead, hey presto, a global flood, abracadabra, ten plagues, shazam, magic bears. In the latter case, to kill children as a punishment for impoliteness.
Again they were not children.
So now you are talking exclusively about God's judgments in this world. Yes, and He's made it clear in the Old Testament that this IS how He operates in this world. This is His Law inexorably judging sin. He also time and time again sends prophets to warn that such judgments are coming so that people can repent and avoid them. They usually don't, at least not on a national scale, so they get zapped but they were warned and that has to be understood as God's mercy.
It took Noah a hundred years to construct the ark and we understand that he preached incessantly to the people to repent of their sins because a great judgment was coming, but they ignored him and treated him as a moron, so when the Flood did finally come only the few who were with Noah were saved.
Nineveh however is an interesting case of a pagan nation that followed idols that DID repent and was spared that judgment preached by Jonah.
If you want God's judgments to stop, you REPENT. If you go on mocking and insulting God and those who believe Him you can't say you weren't warned.
So any theological argument that says that the God of the Bible would take a non-interventionist stance in general has got to be wrong. According to the Bible, he'll use his powers to intervene in the most trivial of human affairs when he feels like it.
Trivial by whose standards? Yours of course. Not His. But like others here you know so much better than God how things ought to be. Which is how all those people Noah preached to also thought.
There are two possible conclusions. One is that most of the time he doesn't feel like it, and sits back and lets things happen that a good human being would give his very life to prevent --- and which God could prevent just by wishing it. The other is that there is no God and the Bible's a load of old cobblers.
Well if you are going to go on ignoring His revelation about how He does things you're going to go on making up stuff about Him and He's going to leave you to it. God is intervening all the time to keep this world from falling into total ruin, as a matter of fact, and He does restrain evil according to the prayers of His people, but this isn't apparent to you because this world IS so overridden with sin and evil. One way God intervenes for our good IS to judge sin. Like the death penalty they can protect us from worse evils and if they led us to repentance which is really what should be our response, then we would be protected from worse calamities to come. I keep watching all the destruction that keeps coming from natural disasters and think how it's only going to get worse because there's never a call to repentance, it's all just ask the government for more money etc. etc. Churches pray but the sin is enormous. You don't understand anything about how He works because you ignore what He's told us, so it looks whimsical to your little mind.
Again, try restraining your own opinions about these things. That's the only way you might come to learn something.
Those are facts. If presentation of these facts suggests some sort of moral judgement to you, then while that may be my intention, it is not my doing. It's yours.
OK so you aren't judging God for not intervening in the rapist-murder? No, you just don't believe He exists. OK, whatever. All the same to me.
He who surrenders the first page of his Bible surrenders all. --John William Burgon, Inspiration and Interpretation, Sermon II.
1Jo 1:3 That which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship [is] with the Father, and with his Son Jesus Christ. 
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