I have just recently learnt why there are still many religious people say that mystical/magickal/psychic practices are the work of the devil. This is so because when a person picks up a mystic skill, their goal is to boast their skills to the entire world. They become so egoistic and selfish, therefore they forget that the ultimate goal to attain spiritual enlightenment (which also includes achieving better experience and skill) is to connect to God. It is only considered pure when a person's reason behind learning a certain skill is for personal spiritual development, and from there their skill also improves and they will become at one with God.

Some might say they want to learn mystical skills to help others, which is actually a good thing, but what drives you to help the other person? Is it sincere charity? or is it just to boost your ego? Give it a good thought.

That is really good food for thought there. I agree. I also believe a lot of it is because many of the major religions today exist to hold people back in fear. Through the use of fear and using such characters as the devil these religions can control people. In controlling these people they do not understand themselves. It becomes a means for keeping certain people in power in that position. Whatever means by which a person does something should be rooted in love and not in fear.

Spirituality is a learned and practiced skill.  When we develop for spirituality, a consequential side effect can be the opening of the psychic abilities.  So the focus for the practices comes first, then the opening to the sensitivities within.

That was exactly what I read from a Yoga website. You seek the Kingdom (God & Spirituality), and then these Siddhi (psychic) powers wil come to you

Unfortunately there are many people who open their natural psychic abilities without the spirituality being opened.  That is where the problems set in.  And the church may dismiss all because of a few.