The problem of evil and immorality is only one argument against the existence of God.
There are many others arguments that are even better.
For example, we are often told that miracles happened often in the past but the evidence shows that they do not happen today.
Why not? Why have the miracles suddenly stopped? A good argument against the existence of God is that if God really existed then he would have to keep the miracles going because otherwise no one would believe that he exists.
Also one could also argue that a God who commits miracles is evil:
Suppose that Jesus miraculously fed and healed thousands, raised someone from the dead, or that God parted the Red Sea to save the Israelites.
Suppose that all of the millions of visitors to the shrine at Lourdes, France who claimed to have been miraculously healed were actually miraculously healed. Suppose that God were to reach out and instantaneously eliminate all pointless suffering in the world today. None of these miracles accomplishes nearly as much as God could: He didn’t do it yesterday, he didn’t do it at Auschwitz in 1945, or when the bubonic plague ravaged and killed millions in Europe during the 1300s. He didn’t do it in countless other cases where all of the morally relevant details were the same as the cases where he is alleged to have performed a miracle.
Christine Overall says, “If Jesus was the Son of God, I want to know why he was hanging out at a party, making it go better [turning water into wine], when he could have been healing lepers, for example.”She concludes, “a being that engages in events that are trivial, capricious, and biased cannot be a morally perfect God.”
She says, “As those who would defend the argument from evil point out, there is a huge amount of evil in the world—psychological and physical suffering, malnutrition, starvation, pandemics, cruelty, torture, poverty, racism, lynching, sexism, child abuse, assault, war, sudden deaths from natural disasters—the list is appalling. . . . Instead of using miracles to feed a small number, to transform water into wine, or to convert a few people, God could very well be performing miracles that have a much larger effect, especially on the lives of the millions of children whose suffering is particularly incomprehensible to anyone with a sense of justice. The question is why a good God would be concerned with details like the need for wine at a wedding, and yet apparently not be concerned with huge tragedies like the holocaust of six million Jews.”
James Keller argues against God’s performing miracles: “The claim that God has worked a miracle implies that God has singled out certain persons for some benefit which many others do not receive implies that God is unfair.” He continues, “there may be two cases which are similar in all ways that seem relevant, yet in one case there will be a recovery (which some deem a miracle) and in the other case no recovery.”
A supernatural being who performs a miracle while idly standing by in the presence of so much suffering in the course of history would be guilty of gross negligence, failing to meet obligations of moral stewardship, and failing to fulfill a duty to rescue. It would be reasonable to conclude that such a being is evil.
Another good argument against the existence of God comes from biology. Biology has shown that the evidence for evolution is overwhelming.
While one can simultaneously believe in Darwinian evolution and in God, evolution is more likely in a Godless world. But the evidence also shows that the process of evolution by natural selection is sloppy and wasteful. More than 99% of all species that ever existed on Earth are now extinct. Also matches of DNA sequence show that humans and gorillas shared a common ancestor.
Miracles didn't happen then, and don't happen now. If miracles occurred in Biblical times then why don’t they occur now?
It is highly suspect to claim that all the shock and awe stuff was only performed for the benefit of ancient, primitive people, but denied to us modern folk, today. Miracle claims initially bear witness against themselves, as they claim to violate the very laws of nature that cannot be violated.
Links:
http://www.provingthenegative.com/2008/05/100-reasons-to-believe-that-god-does.html
http://www.nairaland.com/1150005/library-best-40-atheist-arguments
http://backyardskeptics.com/wordpress/arguments-against-gods-existence/