Faith is, by definition, belief without evidence. Faith is what Religious People fall back on when they can't prove whatever they want to believe about their religion. Most adults know that believing in Fairies, elves, goblins etc is silly and irrational. Believing Mythology of the Bronze Age and Iron Age doesn't make sense either. So why do we respect people who believe in God?
More about faith
More seriously, too many people assume that God is behind things. Then they don't take control of their lives and work to improve things that are wrong in their lives.
- Faith can't move mountains, only geological forces can more mountains.
- Faith also can't move aeroplanes to crash into buildings, simply because it is an idea. People with faith can move aeroplanes into buildings as we found out 9/11.
- Faith can also lead people into self-denial, and other destructive habits, like flaggelation, an advanced form of which we know as Conservatism.
The term faith is usually used to mean religious faith but people sometimes also have faith in secular belief systems like Marxism, Laissez-faire economics etc, this can lead to irrational and destructive political actions.
Faith in Irreligion
- Main article: Faith in Irreligion
Although faith is usually associated with deities and other mythologies, certain varieties of atheism must also be considered a kind of faith (though merely being the void where a religious faith would otherwise be).
Faith is not evidence
Different faith positions are incompatible and they can't all be true.
- Christians have faith Jesus was/is God and part of the Trinity while Muslims believe Allah is God and doesn't have three parts.
- Roman Catholics have faith the Pope is God's representative on Earth while some extreme Protestants have faith that the pope is Antichrist but other Protestants have equal faith The Pope is Not the Anti-Christ!. Then other Protestants believe someone else like an American President is antichrist.
It all gets very confusing but clearly these different faith positions can't all be true at the same time. That shows faith provides no evidence about what is really true, it only shows what believers like to imagine must be true. 
- "Happy is the Man that Feareth Always": Psychology vs. Religion (2005)
- Religion as Faith and Ultimate Concern