Atheism and consistency go together about as well as a jellyfish and a butt cheek. Atheists can often be found bragging about their intelligence, and about how Christians are just gullible "sheeple" while atheists are apparently the most intelligent people in the world who would never fall for such silly fairytales. They're free thinkers, and all their conclusions are rational.
In the very next breath, these same atheists will often tell you that atheism is not actually a conclusion, but rather, just a "lack of belief" in God. Rather than admitting they have religious beliefs, they basically tell us that atheism is about saying "nope, I need more evidence".
These two attitudes do not go together. See, it takes no thought what so ever to lack belief. Even an inanimate object lacks belief. My dog lacks belief in God, meaning if atheism is just a lack of belief in God, even my dog is "smart" enough to be an atheist. If atheism is a lack of belief, it is not a smart position. If it is a smart position, it cannot be just lack of belief.
Of course, in reality, lacking belief may actually be quite foolish. It's one thing to hear a position and withhold judgement until you have gathered enough relevant knowledge to form a conclusion, it's another thing entirely to sit there saying "nope, not enough evidence. Nope, you still need more evidence. Nope..." There is only so long you can continue doing this before it goes from discernment to child-like denial. Just as any dog can lack belief in God, any pre-schooler can put their fingers in their ears and close their eyes in denial.
The ironic thing is that modern evidence suggests children must be taught not to believe in God. One study by Dr Olivera Petrovich, for example, shows that even though Japanese culture typically discourages speculation about the metaphysical, Japanese children typically recognise the world not only as designed, but designed specifically by God. Children have a greater thought process than atheists!
We need not marvel at this, for the Bible shows us rather clearly that human beings were designed with certain theistic instincts. Creation testifies of its Creator, such that nature is often described as "general revelation". Some have even been a bit overzealous and described it as the 67th book of the Bible. Furthermore, with the exception of literal psychopaths, human beings have a natural tendency towards certain views of morality. We tend towards marriage and charity, while we look down on things like theft, adultery, and murder. Though marred by sin, the human race is by no means ignorant of God's presence. As I like to say, in contrast to the "God doesn't believe in atheists" crowd, atheism is real, but it is deliberate.
But why would it be deliberate? What is it about Christianity that would cause a man, consciously or otherwise, to reject it in spite of evidence? The answer the Bible presents is sin. We reject God intellectually because we reject Him morally. He requires us to live in a certain way, yet we want to live our way. Ironically, many atheists stop just short of admitting this by making arguments against the faith based on their dislike of God's morality. Sin, not evidence, is what prevents an atheist from coming to God.
But sin is not going to prevent God from coming to an atheist. See, in His unfathomable glory, God has decided that although sin deserves death, the sinner themselves do not necessarily require punishment. A worthy substitute can take the place of the sinner. Thankfully, one volunteered. Jesus Christ, the Son of God, walked the earth as a man, without sin. He died, taking the full wrath of God against sin. Because of this, anyone who confesses Him as Lord and believes in their heart that God raised Him from the dead will be spared the penalty due to them, receiving instead eternal life. Don't be as derpy as my dog. Confess the Lord, believe He rose, and get baptised.