In chapter 20 of John’s account of the good news, Thomas is quoted as saying, “Unless I see the marks of the nails on his hands, and put my hand into his side, I will not believe.” Many atheists have taken a cue from Thomas and proclaimed that they have no intention of believing in the existence of God unless they see conclusive proof. They say that it is irrational to take things on faith, and we should only believe things that have been proved.
However, this argument neglects the reality that nothing in life has been proved, and everything has to be taken on faith. When you drive your car, you almost certainly have not checked that all the wheel nuts are tightly fastened, but you have faith that the wheels will not fly off, and you trust your life to that belief. Whenever you eat food you have faith that it does not contain poison; whenever you cross a bridge you have faith that it will not collapse. Every day you trust your life again and again to your unproven beliefs.
It is only irrational to have faith in something when the available evidence indicates that it is not true. The vast majority of people who believe in the existence of God do so based on the evidence that they have observed. If the creation of a wonderful world by a God who loves us and wants us to be reconciled to him makes more sense to you than the accidental occurrence of a purposeless universe, then it is irrational not to believe in God.