Happiness has for ever been the prime aim of every human being. All activities of man are directed towards acquiring the maximum happiness in life. But, through the wrong deluded notion that objects will give happiness, man searches for it outside. The result is that in spite of all his lifelong efforts, he gets disappointment only. Vexation and misery alone are to be seen everywhere. The real lasting happiness lies within. Such happiness is Inner Self, The very nature of Atman/soul is pure Joy. This is never perceived because the mind is completely externalized. As long as the mind is restlessly wandering about amidst objects, ever fluctuating, excited, agitated and uncontrolled, this true joy cannot be realized and enjoyed. To control the restless mind and perfectly still all thoughts and cravings is the greatest problem of man. If he has subjugated the mind, he is the Emperor of emperors. For gaining mastery over the mind, you have to know what it is, how it works, how it deceives you at every turn and by what methods it can be subdued.
After all what does a Raja yogi attain by meditation?
A Bhakti yogi by devotion?
A Gyanayogi by introspection?
A Karmayogi by scarification and selfless service?
It is subjugation of mind.
That which separates you from God is mind. The wall that stands between you and God is mind. Pull the wall down and you will come face to face with God. – chhandogya upanishad
The vast majority of men know not the existence of the mind and its operations. Even the so-called educated persons know very little of the mind subjectively or of its nature and operations. They have only heard of a mind.
Doctors know only a fragment of mind. Mind, according to them, is only an excretion of the brain, like bile from liver. The doctors are still groping in utter darkness. Their minds need drastic flushing for the entry into the yogic experiences of mind. It is only the Yogis and those who practice meditation and introspection that know the existence of the mind, its nature, ways and subtle workings. They know also the various methods of subduing the mind.
It is brain that wants rest (sleep), but not the mind. A yogi who has controlled the mind never sleeps. He gets pure rest from meditation itself.
~ Cosmic mind and individual mind ~
Cosmic mind is the sum total of all the minds. The individual mind is connected with the cosmic mind. Cosmic mind, Hiranyagarbha, super conscious mind, infinite mind, and universal mind are synonymous terms. Different authors have used different terms. Do not be puzzled. Do not be confused. The mind, being very subtle, is in close apposition or contact with other minds, though the human skull intervenes between them. As mind evolves, you come into conscious relation with the mental currents, with the minds of others- near and distant, living and dead. The individual mind of A, although separated from the mind-substance used by other individuals, B, C, D, E, X, Y, etc., by a thin wall of very finest kind of matter, is really in touch with the other apparently separated minds and with the universal mind of which it forms a part. If A is a friend of B, A’s mind is connected with B’s mind. The minds of friends, relatives, brothers of A are attached to A’s mind. Several minds are similarly linked to B’s mind also. The minds of those who are attached to A’s mind are, therefore, connected, in turn, with the minds of those who are hanging on B’s mind. In this manner, one mind is in touch with all minds in the whole world. This is the vibhu theory of mind of Raja yoga.
Mind always attaches itself to something objective (gross). It cannot stand by itself. It is only this mind that asserts itself as ‘I’ in this body.
~Functions of mind~
Sensation, thought and volition are the threefold functions of the mind. Cognition, desire, volition are the three mental processes. Mind has three states, viz. active, passive and neutral. Mind always wants variety and new sensations. It is disgusted with monotony. Law of Association, Law of Continuity and Law of Relativity are the three principal laws of the mind. Thinking, planning, feeling, knowing are the various activities that are going on in the mind. Sometimes you plan. Sometimes you feel. Sometimes you try to know. Sometimes you think seriously. Sometimes you will (volition). Volition brings all the mental faculties into play. You must be able to know by introspection what exactly is going on at different times in the mind.
Just as the physical body is composed of solid, liquid and gaseous matter, so also the mind is made up of subtle matter of various grades of density with different rates of vibration. A Raja Yogi penetrates through different layers of mind by intense Sadhana. The mental body varies much in different people. It is composed of coarse or finer matter, according to the needs of the more or less unfolded consciousness connected with it. In the educated, it is active and well-defined; in the undeveloped, it is cloudy and ill-defined..
Mind has got aura (spiritual aura). Aura is Tejas, brilliance or halo that emanates from the mind. The aura of those who have developed their minds by turning inwards (towards soul) is extremely effulgent. The spiritual aura is more powerful than the psychic/ Pranic aura…
~Mind a subtle matter~
Mind is the most important element of the astral body that is linked to the physical body through physical Prana. It separates itself at death from the physical body and travels to Subtler planes. It is this body that comes and goes. This body melts in disembodied salvation. Mind is subtle matter. This discrimination is made on the principle that the soul is the only source of intelligence; it is self-evident; it shines by its own light. But the organs (mind and senses) derive their principle of activity and life from the soul. By themselves, they are lifeless. Mind is merely reflecting the consciousness like water reflects the light of sun, water itself is not the source of light so is the mind.
Ref- Mind – It’s Mysteries and Control—-Swami Sivananda Saraswati