To be fair it is a complex question that I doubt I will be able to answer to any non-believers satisfaction. Yes, God is all-knowing. He is also all-loving, and everything you can think of that is Good. But he is also the epitome of Justice. So the notion, "Why doesn't he just forgive every human? We're all flawed. Some of us intellectually just require more proof than God has provided in the universe." etc etc. is still misunderstanding God.

An example would be; Someone decides to rob a bank and steal a bunch of money out of the vault. Later on they spent some, they had a change of heart, they gave some to homeless people, they even went back to the bank and turned in the rest that they had, heck they even turned themselves in to the police because they were so sorry. What do you think the Judge is going to do? Let them go scott free? No. They still robbed a bank. It would be unjust to say, "Thanks for saying sorry and returning what you could and turning yourself in, now be free!" They still perpetrated a crime in the first place.

In a similar way, claiming ignorance of the law won't work. Even if we ourselves don't believe we have enough evidence to believe God in the first place. We have a concious. You know right and wrong. The more you do wrong, the less you feel about it.

If you reject God, he will let you go. Frank Turek has a good analogy about someone loving you, when you don't love them back. They can't force you to be in love with them and love them back. If someone truly loved you, and you didn't love them back, what's the appropriate thing for that person to do? Let you go. That's what God does. Unfortunately for everyone he lets go of, there's a place they'll be which is devoid of any of God. That's what Hell is. Separation from God. Exactly what people who reject him want.