Belief is a natural tendency to accept knowledge without doubt. Every soul is born with this tendency to accept every knowledge that is given to it, in whatever way or form. Therefore no soul in the world is born an unbeliever.

There is a saying of the Prophet, "Every soul is born a believer, and it is others that make the soul an unbeliever."

This unbelief comes by the conflict of one's knowledge and belief.

Belief has two tendencies. One is the tendency of water that runs and the other is that of water that becomes frozen.

Some people who have a belief like to keep that belief unchanged as a rock, and identify their ego with that belief. People of this temperament are steady in their belief, but often they lack progress. If they happen to have a right belief, there is no danger of their giving it up; but if it is not right, they are perplexed.
Those whose belief is like running water perhaps go from one belief to another, and they may not seem steady in their belief, yet their life is progressive. The progressive soul can never hold one belief, and must change and go on changing until it arrives at the ultimate truth. For a simple person steadiness of belief is more advantageous than change, for change may lead him astray. But for an intelligent person it is natural and necessary that he must go from belief to belief until he arrives at his final convictions.

Belief is of four kinds.

The first kind is a belief accepted because it is believed by all.
The second is a belief accepted because it is believed by someone in whom the believer trusts.
The third belief is the belief that reason helps one to believe.
The fourth belief is conviction of which one is as sure as if one were an eyewitness.

The four kinds of belief are held by souls of different grades of evolution in life and different temperaments. There is a knowledge which one can perceive with the senses; and there is a knowledge which one can perceive with the mind alone; and a knowledge which can be realized by the soul. And it is for this reason that when a person wishes to touch a thing which can only be perceived, and when a person wishes to feel a thing which can only be realized spiritually, he naturally becomes an unbeliever.

In point of fact one person's belief cannot be another person's belief; every belief is peculiar to the person who holds it. Even if two persons held one belief, there would still be the difference of the point of view, even though it be as small as the difference between two roses. Therefore it is unjust, no doubt, on the part of one person to try to press his own belief on another. At the same time the person who refuses to try to understand the belief of another, from bigotry or pride, closes the door of his heart, that otherwise would have let that knowledge come in.

There are two tendencies that can be developed in a person, either constantly to try to believe whatever comes before him, or to try to disbelieve whatever is presented to him. And there is an advantage and a disadvantage in each of these tendencies.

The advantage of the believing tendency is the taking of every chance of acquiring knowledge, the disadvantage is that one takes the chance of often and readily falling into error.
But the advantage of the disbelieving tendency is only the protection from error, and its disadvantage is the prevention of every chance of further acquisition of knowledge.

Nature has very many covers; its activity covers and uncovers it. At every covering and uncovering, it is natural that the belief of the individual should change. Therefore when a Sufi is asked, "Do you believe in this, or that?" he says, "My belief is for me, yours is for you, there is no faith to which I give my unchanging belief, nor any belief that I reject without having investigated it." If you are asked, "What belief does the Sufi teach?" you may say, "No belief, but he helps the pupil to seek and find within himself his own belief."