The first five are called external aids (bahiranga sadhana) and the latter three are called internal aids (antaranga sadhana) to yoga.In this framework, we have to keep in mind that Yoga is more than just a physical discipline. It is a way of life—a rich philosophical method of playing the game of life. Let us look into these eight steps more closely.
1. Yama:
The first constituent of Ashtanga Yoga is universal vows (yamas) which are five in number. They are universal because they are not limited by class, creed, time or circumstances. They are the guidelines as to how we interact with the outer world. They are the social disciplines required for our relationships with others. These are:
Ahimsa or non-violence is the awareness and practice of non-injury or harm to others or even to one’s own self in thought, speech and action. It advocates the practices of compassion, love, understanding, patience, self-love, and worthiness. Patanjali describes truthfulness as: "To be in harmony with mind, word and action, to conduct speech and mind according to truth, to express through speech and to retain it in the intellect what has been seen, understood or heard." A perfectly truthful person is he who expresses in his speech exactly what he thinks in his mind and in the end acts according to it.
Non-stealing or asteya implies relinquishing of the undesirable possession of thought, speech and action. Asteya stands against covetousness and envy. It advocates the cultivation of a sense of completeness and self-sufficiency in order to progress beyond base cravings. Celibacy or Brahmacharya is a behavior, which brings man nearer to the Divine. This yama believes in avoiding all sensual pleasures, whether mental, vocal or physical. Non-covetousness is the non-accumulation of worldly objects, caused by possessiveness and attachment.
2. Niyama:
The niyamas are the second constituents of Ashtanga Yoga. They are also five in number. They help us as to how we interact with ourselves and our internal world. They are self-regulatory in nature. They help us maintain a positive environment in which we grow. They channelize the energy generated from the cultivation of the earlier yamas. The five niyamas specified by Patanjali are:
Purity implies both external as well as internal purity. In the words of sage Manu, water purifies the body; truthfulness the mind; true knowledge the intellect and the soul is purified by knowledge and austerity. Contentment is described as not desiring more than what one has earned by his honest labor. This state of mind is about maintaining equanimity through all that life offers. Contentment involves the practice of gratitude and joyfulness - maintaining calm at all costs. This state of mind does not depend on any external factors. Austerity is described as power to withstand thirst and hunger, cold and heat, discomforts of place and postures, silent meditation and ritual fasts. It also maintains that the perfect man is he who practices body discipline and thereby mental control. Self-education consists of scriptural studies. Meditation on the Divine, the last of the niyamas, is the dedication of all our actions, performed either by intellect, speech or body, to the Divine. It is the surrender to the Divine.
The benefits of practicing Yamas and Niyamas are that they help us in managing our energy in an integrated manner, harmonizing our external life and our inner development. They assist us in respecting the values of this life. In short they mould us to lead a conscious and contended life ever connected with the Divine.
3.Asanas
Yogasana means discipline of the body. It is a posture to keep the body free from disease and to preserve vital energy. Correct postures are a physical aid to meditation. Asanas have a range of therapeutic uses for helping in balancing and harmonizing the basic structure of the human body. Performance of a perfect yogasana leads to the absolute intellectual absorption of the mind on a single task (dharana), which in turn leads to the fusion of the individual spirit with the Divine Self (dhyana).
4. Pranayama
'Pranayama' is a compound term ('prana' and 'yama') meaning the maintenance of prana in a healthy manner throughout one's life. More than a breath-control exercise, pranayama is all about controlling the life force or prana. It leads to a state of inner peace. Hatha Yoga deals with this subject in an extensive manner. Pranayama is a technique, which re-defines our breathing process, helps us to release tensions and develop a relaxed state of mind. It also balances our nervous system and encourages creative thinking. In addition, by increasing the amount of oxygen to our brain it improves mental clarity, alertness and physical well being. It is highly conducive to the concentration of the mind.
But one has to carefully note that it is always advisable to be aware of all the do's and don'ts of Pranayama and Yoga Asanas before starting to practise them. They have to be performed only under the proper personal supervision of a qualified guide as otherwise they are likely to produce more harm than benefit..
5. Pratyahara
Pratyahara is the withdrawal of sense organs from their external objects. It involves rightly managing the senses and going beyond them instead of simply closing and suppressing them. It involves reining in the senses for increased attention rather than distraction. It is essential to practice pratyahara for achieving the meditative stages of dharana, dhyana and samadhi. These three final disciplines are actually three continuous steps of the same process.
6. Dharana
Dharana involves developing and extending our powers of concentration. This consists of various ways of directing and controlling our attention and mind-fixing skills, such as concentrating on the chakras or upon a physical object such as the flame of a lamp, the mid point of the eyebrows or the image of a deity etc.
7. Dhyana
Dhyana is the state of steadfast meditation, when the mind attains the ability to sustain its attention without getting distracted. It is an undisturbed flow of thought around the object of meditation where the act of meditation and the object of meditation remain distinct and separate. Strictly speaking, this is a state of mind, a delicate state of awareness. This state rightfully precedes the final state of samadhi.
8. Samadhi
Samadhi or total absorption is the ability to become one with the True Self and merge into the object of concentration. In this state of mind, the perceiver and the object of perception unite through the very act of perception - a true unity of all thought and action. It is oneness with the object of meditation; there is no distinction between act of meditation and the object of meditation. This is the culmination of all yogic endeavors—the ultimate 'yoga' or the yoke between the individual and the universal Soul, merger of the jivatma into the paramatma, the supreme identity of the individual soul with the Divine.
Patanjali's Yoga Sutras categorize and grade the levels of samadhi in the first chapter. Samadhi is of two kinds viz.
1. Samprajnata Samadhi or conscious contemplation and
2. Asamprajnata Samadhi or superconcsious contemplation.
In the first case, the mind remains concentrated on the object of meditation and therefore the consciousness of the object of meditation persists. Mental modifications arise in respect of this object of meditation. In the second case, the mind (chitta) and the object of meditation are fused together. The consciousness of the object of meditation is transcended. All mental modifications are checked although latent impressions might continue.