Imagine you wanted to create a religion that was almost impossible to abandon. Threats might come to mind. Many religious threaten apostates with far greater consequences than does Christianity. Yet Christianity does include one powerful hurtle to abandoning Christianity that prevents the Christian mind from honestly considering any proposed weaknesses of Christianity. This is the notion that doubt is improper or is inferior to belief. While strong belief is praised and encouraged, doubt is considered a character flaw. The book of James, while specifically referencing the believer asking for wisdom, gives as a universal reason to condemn the doubter the claim he is “unstable in all his ways”.
But when you ask, you must believe and not doubt, because the one who doubts is like a wave of the sea, blown and tossed by the wind. That person should not expect to receive anything from the Lord. Such a person is double-minded and unstable in all they do. (James 1:6-8)
Does this claim by James conform to rational belief? Are we not justified in doubting to the degree that the evidence is lacking? Would not the Christian advise the Muslim to doubt their beliefs? How could one ever honestly reexamine their beliefs if they are encouraged not to doubt? Would a rational God condemn the rational doubt that must exist where there is less than absolute evidence?
Rational belief is a degree of belief that maps to the degree of the relevant evidence. Where there is less than absolute evidence, there must necessarily be a degree of doubt. To have no doubt when the evidence is less than certain is to be irrational. Doubt, instead of being inferior to belief, is equal to belief. A degree of belief exceeding the degree of the evidence is irrational. A degree of doubt falling shorter than the degree of the evidence is irrational. Belief commensurate to the degree of evidence is rational. Doubt commensurate to the degree of the lack of evidence is rational. There is nothing intrinsically undesirable or improper about doubt.
In the alleged story in which Thomas increased his degree of belief after actually touching the resurrected Jesus, Jesus did not bless Thomas for maintaining doubt until there was stronger evidence. Jesus instead blessed those who would believe without seeing.
Then Jesus told him, “Because you have seen me, you have believed; blessed are those who have not seen and yet have believed.” (John 20:29)
Would an actual God of the universe treat doubt, a necessary element of rationality, in this fashion?
(See also #20 and #21.)
ADDITIONAL NOTES:
Another biblical passages to consider is Hebrews Chapter 11. Those with high degrees of belief are applauded, but no praise is afforded those who are skeptical. More importantly, observe the way belief is treated as something binary: either it’s on or off. This is not rational belief since rational belief must necessarily map to the degree of the evidence. And evidence arrives incrementally for things inductively assessed.
A verse in 2 Corinthians makes it clear that Christianity is not about evidence, but about belief regardless of what evidence is or is not seen.
For we live by faith, not by sight. (2 Corinthians 5:7)
This encouragement to muster a high degree of belief regardless of the degree of evidence, and the implication that this act is somehow virtuous simply highlights the fact that the Bible does not appear to have been written by a rational God.
P1: Any ideology that values belief more than doubt is irrational.
P2: Christianity values belief more than doubt.
(See James 1:8)
Conclusion: Christianity is irrational.
{P1 & P2}
Sufficient Reasons To Consider Leaving Christianity 