Carl Jung, an expert in Eastern spiritual and meditative practice, had warned against Westerners (which for practical reasons encompass almost every modern man by now) mimicking Eastern spiritual practice. Why? Without a tradition of religious morality behind such practices, a student of Eastern practices may end up with ego inflation at best, psychotic at worst. Why? Bits of unconscious when allowed to surface will become autonomous. When such bits come from the darker side of our unconscious, a person can result in an inflated ego, or even an evil ego. And when such bits are pathological, which can be more prone to be for certain people, an unsuspected novice can become psychotic.
Unfortunately in our contemporary secular culture, meditative practices tend to become amoral - in order to attract a larger audience. Happiness becomes an ultimate objective. To relax our mind and body so that we can be refreshed to earn more money (and power!) also becomes an ultimate objective. "Why enroll if your meditation (spiritual) course cannot deliver some tangible benefits for me?" And our customer has the right to ask and to demand, afterall it is a free and consumerist society.
Traditional Eastern practices have always put morality as a prerequisite to any meditative practice seeking for enlightenment and spirituality. For example, according to the Dalai Lama, the first meditative focus shall be compassion or similar moral concepts. In Sufi, a student has to follow 100% the demands of his teacher, who presumably will instill moral behavior, and concepts, to the receptive mind of his student before any spiritual enlightenment approach begins. Buddhist monks under Zen masters shall follow moral rules and disciplines.
In Jungian approach to spirituality as per Marie-Louise von Franz and C.G. Jung Institute in Zurich, such dangers have been raised. Unfortunately in the West, direct spiritual experience has not been part of main stream religious tradition. And when coupled with our contemporary secular thinking, new age spirituality pursues can easily become "doing good things for others, ultimately for the benefits of one's selfish self" even when "morality" and "good deeds" are put onto the agenda, with possible negative effects as explained above.
Carl Jung's warning is still sound, perhaps even sounder now, as almost all of us belong to the West nowadays.