Just about any religious text is a corrupt document. It's already documented that the New Testament was changed during translations (including adding the "let he who is without sin throw the first stone" story; it's a great summary of some of Jesus's teachings, but it wasn't initially there and probably never happened), and you have to imagine that the Old Testament is going to be even worse (when people were even less educated and perceptive of the things around them, or were prone to fabricate details and possibly entire stories; for example, it's pretty absurd to suggest that people towards the beginning of the Bible's history used to live for several hundred years).
Regarding the article that was linked in the first post, it's a compelling argument, but there are some details that it does not give justice:
1) Regarding Argument #2, when people prove themselves to be "good" or "evil," the reality is that pretty much everyone will be neither perfectly good or perfectly evil. It seems to be a bit weak to suggest that someone who is typically good but fails to excercise good judgement a few times is necessarily damned to Hell (as the word "purgatory" never shows up in that essay).
2) Regarding Argument #3, a just God doesn't necessary have to intervene to punish evildoers on this plane of existence. Besides, a God not doing so forces us to be proactive in protecting ourselves and administering justice (of course, this is an imperfect art) and keeps us from being lazy. But if there's a God, it may simply be a matter of its power not being placed in this domain; it's relevance may only come into play in an afterlife.
3) This point concerns Argument #3, and it ties into my opening rant as well, but if there's a God, it may very well have nothing to much if any of what is said in the Bible. The God that asked Abraham to kill his son may be a false God, although that doesn't necessarily mean this is the same God that was observed in any other given part of the Bible.
4) Regarding Argument #4, there will be a lot of moral people who will be willing to test their faith, but even if the "right" conclusion is to conclude there is no God, they simply lack the luxury of time to properly assess and shape their values to come to that conclusion. If they work long hours and/or die young (or lack a good education), well-meaning people may simply not get that opportunity, and it's not necessarily their fault. Of course, more is expected of those with more idle time (ironically, we at least see the merit of the idea that it's easier for a camel to fit through a needle's eye than for a rich person to get into heaven).
I suppose I'm still an agnostic as the article suggests I am supposed to be if I am to be good, but the reasoning I take is a bit different. The article concludes directly that there's no credible evidence for a just God, but there's a point to be argued first. It's that the number of questionably moral things God does (or is said to have done), plus a number of other logical/situational absurdities, invalidates the Bible as a document to be taken literally. The same can be said for really any other major religious document/compilation, so it would *then* follow that there probably isn't a just God, because there's no credible evidence of there being one (since all documents supporting that notion can be proved flawed, at least in a literal sense).
But this doesn't keep believers out. It's naive to think that all just people should come to the same conclusion, because they are exposed to different stimuli and are placed under different constraints as we are. Besides, the important thing isn't us judging others regarding whether they would get into heaven (if there is one), but for us to show the love, compassion, and understanding that we ought to be showing (not in order to get into heaven, but because we want to), which in turn should help them do the same as they become stronger.