I use emotion for the many and reserve reason for the few.
Looking back on my conversion to Christianity, and also on my experiences as a believer; I have come to the conclusion that the reason that Christianity is so successful is that it appeals to the emotions. The above statement by Adolf Hitler is one of the many reasons that you can't, try as you might, appeal to reason to convince a believer about the falsity of their beliefs.
One fact that is known is that most believers did not come to theism by reason. Christianity is a religion that provides hope in a better tomorrow. It promises eternal life, joy, and the elimination of today's evils such as sickness, death, suffering, pain, etc. It tells its adherents that they will have all of these things and more, but the biggest prize of them all is that you will get to dwell in the presence of the Lord! Christianity promises what every sane person on this planet desires; the chance to live in peace, prosperity, and health.
The many authors of the Bible sought to provide hope in a time of strife, even if those hopes were false. As I said in an earlier post Christianity is a Jewish sect and its promises stem from the suffering, turmoils, and strife that the Jewish people have endured. In the Old Testament for instance there are promises of a messiah who will crush all of their enemies and bring the Hebrews back to their prestigious place as God's chosen people. When reading the scriptures you must always keep in mind the circumstances of the time period that the author was writing in.
During the time of the authorship of the N.T. the Jews were under Roman rule. They believed then as they always have that Yahweh would deliver them from their oppressors. The N.T. authors were playing off of the same themes found throughout the O.T. and used those themes as the basis for their new sectarian beliefs. Many of Jesus so called sayings are actually plagiarized from the Old Testament and ripped out of context to fit into the narrative in which it is placed.
Many Christians today believe that when they die that they will be united with lost loved ones from this life. They believe that all of the suffering, loss, hardships, injustice,pains, and heartaches of this life will be over and something that would not even be remembered when they find themselves enjoying eternal bliss. Christianity like Judaism is about the hope of a better tomorrow. Psychics and scam artists get rich off of the gullibility of the people and their same desperation to wanting something better out of life.
When I was a believer I found solace and peace in my beliefs. It helped me to know that everything happened for a purpose, that God was in control of it all and that: "And we know that in all things God works for the good of those who love him, who have been called according to his purpose." Romans 8:28 No matter how bad things seemed for me I had my hope and trust in God that in the end things would all work out according to his purpose.
I remember when I used to sing hyms in church or in private how they brought tears to my eyes and seemed to have a comforting and soothing effect on me. All the songs were about how unworthy I was to have God's love and forgiveness, how guilty I should have felt about the Lord's death because of my sinful ways. I was supposed to be grateful and overjoyed that God chose me to serve him and proclaim his gospel. But in my blind ambitions to serve the Lord I did not hold him accountable for all of the things he had done against man.
The church tells you that God is love, but they don't often inform you that he is also portrayed in the scriptures as a consuming fire. The Old Testament is full of themes about divine justice, vengeance, etc. The O.T. deity makes mans worst criminals, dictators, and tyrants seem tame in comparison to the good Lord. Christianity flourished and continues to do so because it provides hope for the downtrodden. In essence it is nothing more than a placebo for humanity's ills.
Note: All biblical citations are taken from the New International Version of the scriptures.