Below is my answer on Quora for the question: ‘Why do some Christians think Christianity is better than Buddhism?‘
I am neither Christian nor Buddhist. But since I am from a country where competitive religiosity is rampant, I think I have a fair view of the issue. I can’t claim to properly understand how Christians in a Christian-majority country might behave. So consider what follows an educated guess.
The difference, in essence, between Christianity and Buddhism is that the former is a devotional path that encourages reliance on an external deity and the latter is a philosophical path that advocates exploring one’s own self. So the comparison here is really between the devotional path and the self-exploratory path. Without going into detailed analyses of the two paths, let me just focus — because that is what the question demands — on why followers of the devotional path might consider the self exploratory path inferior.
Devotional religiosity is very seductive. It is all about feelings and the heart. And as is the case with many things of the heart, it is very hard to argue against emotionally. It grips the believer’s heart and can convince him of the righteousness of his cause even when the said cause is patently ludicrous or dangerous to those around him. In the case of Christianity, the devotee is usually someone who believes that Jesus was the son of god and that he died for the sins of all people everywhere. Believing that this is true gives them a very strong advantage in the form of an psychological anchor. It seems odd when you look at it this way, but it is possible to sail through most life’s problems if you have the luxury of giving credit to or blaming external factors. It makes life simpler. On the plus side, it makes people humble and less arrogant. On the minus side, it makes people suspicious of knowledge and unwilling to deal with objective reality.
Self-oriented religiosity can be an equally seductive idea, but that often depends on how willing the individual is to acknowledge his individuality. In some situations (especially situations involving the aforementioned devotional culture) individuality is sacrificed in service of the community / society. Self-oriented religiosity lacks the advantage of communally reinforced beliefs. Individuals have to make do with the knowledge that their own explorations bring them. They do not have the luxury of putting the onus on an external deity and putting forward the faith argument. Note that none of this means Christians and Buddhists can be neatly clubbed into the devotional and individualist categories. It is possible for Christians to be individualists (by treating the Jesus story as only a moral fable) and Buddhists to be devotional (by putting their trust in the Buddha and not his teachings).
This is a general argument, not a specific one. It compare ideologies, not all the possible ways they may be implemented.
Having thus seen the difference, it should be clear why a devotional-path Christian might find a self-oriented Buddhist inferior. Part of the reason why a devotee will look down upon an explorer is because the latter does not follow commandments. Since the devotee’s entire world view is predicated on obeying a set of rules that come from an external agency (the Abrahamic god, father of the aforementioned Jesus), he or she would naturally find the idea of a human being deciding for himself / herself the path that he should take absolutely blasphemous. Especially since the commandments that the devotee is supposed to follow are rather strict and leave little room for maneuvering.
Another reason a devotee might consider the explorer inferior is because the explorer, by merely being himself or herself, poses an unspoken question to the devotee’s way of life. The explorer makes the devotee wonder if he is right. If the devotee’s god is an absolute authority and if his word is law, then how does the explorer go about his life without drawing any punishment upon his person? And if he can do so, then might it not be possible for the devotee to go about exploring his self as well? This creates doubt in the devotee’s mind and doubt, the devotee is convinced, is the opposite of faith. And so the devotee blames the explorer for challenging his faith and through it, his god.