The answer is simple: It’s because spirituality is opposite to us, to our essence, to our egoistic nature. Egoism rules over us; we wish to fill it. Hence, out of everything that surrounds us, we only see what we want to see in our egoism: something pleasant or, at most, threatening.
This is why a person who wants to reveal the upper world, to discover what surrounds him but remains undetected in his egoistic perception, needs to reconstruct himself. For this reason the environment is so critical for a person: It helps to rebuild one’s perception, to attune oneself to the importance of perceiving what is unpleasant to egoism, opposite to it. Then one will be able to witness a wide world that has always surrounded him or her. It is called the spiritual world because it is above the egoistic one.
It seems to us that our views are the result of our experience, but they are the upshot of the accumulation of information convenient for our egoism. And it makes no difference what they say, the truth or a lie: For us the truth is what coincides with our opinion—egoism.
We always look only for what supports our opinion and reject what opposes it. Ultimately, we form ourselves and do not wish to change. Only suffering, the attempts to find the meaning of existence, and a strong spiritual environment, the group, will help a person to become objective, to replace the egoistic perception with the environment’s opinion. And then the upper world that has always existed around him will open for him!