Again, it's not something you KNOW, but something you BELIEVE to make yourself feel good too. You have a fear that you'll not end up knowing the truth after you die, and that there'll just be darkness and silence after you die. You fear the feeling of being left empty handed when you expected to become an omniscient being and know the truth of it all. So you hang on to a belief that if you have faith in this so called concept of "God", then he\she\it will provide the answers for you.
In the end, it's all a way of trying to convince ourself of finding an answer we might never find. Believing in what you believe and keeping it to yourself is the right thing to do. It's best not to try and prove to the unbeliever of your concept to believe in yours by providing ZERO facts.