Kriya yoga is the science of self unification with the Infinity by fulfilling a specific action or ritual. The yogi that practices Kriya Yoga will free himself from the karma or the universal chain of causality. Along with Hatha yoga, Raja yoga, etc Kriya yoga is one of the 6 basic yoga branches. It has many in common with Hatha Yoga or with Ashtanga Yoga.
During meditation and practice the blood releases carbon oxides and loads with oxygen. The oxygen becomes vital energy. This rejuvenates the brain and the spinal centers. Pantajali says that “through pranayama the separation of the inhaling and exhaling flow is done and in this way making possible to achieve a state of spiritual liberation.”
It is believed that historic prophets like Elijah, Jesus and Kabir have dematerialized their physical body through kriya yoga meditation techniques. Also, St. Paul knew kryia yoga or a similar meditation technique because he was saying that he dies everyday by the pride he has in Lord Jesus Christ (see Corinteni 15:31). By retreating daily his vital flow he unifies with the eternal happiness of Jesus Crist consciousness. In this state of high beatitude he is fully aware of being death for the misleading world of ruled by the senses, maya.
In the first experiences of communion with God the yogi consciousness unifies with the Cosmic Spirit, the vital force is retreated form the physical body, that becomes immobile, rigid but the yogi is fully aware of this. It is a state similar with yoga nidra of conscious deep sleep. Later on, with gaining experience, the practician cant achieve more profound states without installing the immobility state.
Kriya Yoga, differing from Yyengar yoga, Hatha Yoga, Raja Yoga or Ashtanga Yoga, Kundalini yoga directs the energy circular around the 6 spinal centers of the body. This spinal centers are correlated with the zodiacal astral signs, symbol of the Divin Cosmic Human. A rotation with a half of minute of the energy around one spinal center conducts to the acceleration of that person evolution. This is equal to one year of normal spiritual evolution.
On a interior aspect the human being is characterized by 6 interior constellations that gravitate around the central point represented by the spiritual omniscient eye. These constellations are related with the 12 zodiacal signs. The human spiritual evolution is made in cycles of 12 eyers each and it is necessary o period of 1 billion years of normal spiritual evolution to reach the state of cosmic consciousness.
Kriya yoga is not about holding as mush as possible ones breath and it is accompanied, from the beginning, by a state of calmness, peace. There is a connection between the rhythm of the breath and the consciousness state. The breath rhythm is at a low level the attention is focused on something and is higher is case of strong emotions like fear, anger, etc. The tortoise, that lives up to 300 years has a breath of only 4 times per minute, while we have 18 breaths/minute.
By identifying with the superficial ego, the human believes that he is what he thinks, what he wishes, what he feels, what he eats or what is keeping him alive without recognizing that his actions are noting but a puppet pulled by strings of past actions, that is karma. All that are feelings, reactions, thoughts are the result of the past or of the previous lives. Above all of these is the regal soul. The human is living soul not vanishing body.