Dhyan Yoga (meditation) is a vigorous tonic to the body systems. Modern science has acknowledge the relationship between the mind’s power and the body systems. From centuries Yogic Scholars has demonstrated mental control over involuntary body actions as heart beats, respiration and blood circulation.
That state of the mind wherein there are no sensual thoughts is meditation. There is continuous current (Pravaha) in the mind of one object. There is only one Vritti (wave of thought) in the mind. It is Ekarupa-Vritti-Pravaha.
Meditation is the keeping up of an unceasing flow of God-consciousness. It is the flow continuous thought of one thing or God or Atman. All worldly thoughts are shut out from the mind. The mind is saturated with Divine thoughts, of Omni presence. Meditation is regular flow of thought with regard to the object of concentration.
To learn the science of self-control, meditation is helpful. Its constant practice possesses a steady mind. Fixing the mind in self, helps in enlightenment of God presence in self. By practicing, one will have the feeling of divine presence.
There are seven steps of enlightenment (seven chakras) in the ladder for Dhyan Yoga (meditation).
The chakras are thought to vitalize the physical body and to be associated with interactions of a physical, emotional and mental nature. They are considered life energy or prana which is thought to flow among them along pathways called nadi (channel). The function of the chakras is to spin and draw in this energy to keep the spiritual, mental, emotional and physical health of the body in balance.7 Chakras
There are believed to be seven major chakras, which are arranged vertically along the axial channel (sushumna nadi). Below is a description of the seven chakras, with various associations. The meditation aspirant needs to follow the path to energize chakras in pattern from the bottom to top. They are as:
Muladhara or root chakra is symbolized by a lotus with four petals and the color red. This center is located at the base of the spine in the coccygeal region. It is said to relate to the gonads and the adrenal medulla, responsible for the fight-or-flight response when survival is under threat.
Muladhara is related to instinct, security, survival and also to basic human potentiality. Physically, Muladhara governs sexuality, mentally it governs stability, emotionally it governs sensuality, and spiritually it governs a sense of security. Muladhara also has a relation to the sense of smell.
This chakra is where the three main nadi separate and begin their upward movement. Dormant Kundalini rests here.
Svadhishthana or sacral chakra is symbolized by a white lotus within which is a crescent moon, with six vermilion, or orange petals.
This chakra is located in the sacrum and is considered to correspond to the testes or the ovaries that produce the various sex hormones involved in the reproductive cycle. Svadhishthana is also considered to be related to, more generally, the genitourinary system and the adrenals. The key issues involving Svadhishthana are relationships, violence, addictions, basic emotional needs, and pleasure. Physically, Svadhishthana governs reproduction, mentally it governs creativity, emotionally it governs joy, and spiritually it governs enthusiasm.
The seed mantra is Vam.
Manipura or solar plexus/navel chakra is symbolised by a downward pointing triangle with ten petals, along with the color yellow.
Manipura is related to the metabolic and digestive systems. Manipura is believed to correspond to Islets of Langerhans, which are groups of cells in the pancreas, as well as the outer adrenal glands and the adrenal cortex. These play a valuable role in digestion, the conversion of food matter into energy for the body. The colour that corresponds to Manipura is yellow. Key issues governed by Manipura are issues of personal power, fear, anxiety, opinion-formation, introversion, and transition from simple or base emotions to complex. Physically, Manipura governs digestion, mentally it governs personal power, emotionally it governs expansiveness, and spiritually, all matters of growth.
The seed mantra is Ram.
Anahata or heart chakra is symbolised by a circular flower with twelve green petals called the heart-mind. Within it is a yantra of two intersecting triangles, forming a hexagram, symbolizing a union of the male and female.
Anahata is related to the thymus, located in the chest. The thymus is an element of the immune system as well as being part of the endocrine system. It is the site of maturation of the T cells responsible for fending off disease and may be adversely affected by stress. Anahata is related to the colours green or pink. Key issues involving Anahata involve complex emotions, compassion, tenderness, unconditional love, equilibrium, rejection and well-being. Physically Anahata governs circulation, emotionally it governs unconditional love for the self and others, mentally it governs passion, and spiritually it governs devotion.
The seed mantra is Yam.
Vishuddha or Vishuddhi, or throat chakra is depicted as a silver crescent within a white circle, with 16 light or pale blue, or turquoise petals.
Vishuddha may be understood as relating to communication and growth through expression. This chakra is paralleled to the thyroid, a gland that is also in the throat and which produces thyroid hormone, responsible for growth and maturation. Physically, Vishuddha governs communication, emotionally it governs independence, mentally it governs fluent thought, and spiritually, it governs a sense of security.
The seed mantra is Ham.
Ajna or third-eye chakra is symbolised by a lotus with two petals, and corresponds to the colors violet, indigo or deep blue, though it is traditionally described as white. It is at this point that the two side nadi Ida (yoga) and Pingala are said to terminate and merge with the central channel Sushumna, signifying the end of duality, the characteristic of being dual (e.g. light and dark, or male and female).
Ajna (along with Bindu), is known as the third eye chakra and is linked to the pineal gland which may inform a model of its envisioning. The pineal gland is a light sensitive gland that produces the hormone melatonin which regulates sleep and waking up, and is also postulated to be the production site of the psychedelic dimethyltryptamine, the only known hallucinogen endogenous to the human body. Ajna's key issues involve balancing the higher and lower selves and trusting inner guidance. Ajna's inner aspect relates to the access of intuition. Mentally, Ajna deals with visual consciousness. Emotionally, Ajna deals with clarity on an intuitive level.
The seed mantra is OM.
Sahasrara or crown chakra is generally considered to be the state of pure consciousness, within which there is neither object nor subject. When the Kundalini energy rises to this point, it unites with the male Shiva energy, and a state of liberating samadhi is attained. Symbolized by a lotus with one thousand multi-coloured petals, it is located either at the crown of the head, or above the crown of the head. Sahasrara is represented by the colour white and it involves such issues as inner wisdom and the death of the body.
Its role may be envisioned somewhat similarly to that of the pituitary gland, which secretes hormones to communicate to the rest of the endocrine system and also connects to the central nervous system via the hypothalamus. The thalamus is thought to have a key role in the physical basis of consciousness. Sahasrara's inner aspect deals with the release of karma, physical action with meditation, mental action with universal consciousness and unity, and emotional action with "beingness."
Dhyan Yoga greatly reduces stress levels and acts as powerful tool to relax nervous system and the body as whole. Meditation helps destroying all causes of sorrow. It helps in mitigating all pains, suffering, sorrow and provide an approach to enlightenment. Meditation gives vision of unity and induces sense of oneness.