A.This body and this condition of mind are both the results of effects of past Karmas. What is Karma? A Vasana or desire arises. Then you exert to possess the object. This is Karma. Thought itself is the real Karma. Physical action is only its manifestation. Then you enjoy the object. This is Bhoga. This Bhoga strengthens and fattens the Vasana. The Chakra or wheel of Vasana, Karma, Bhoga, is ever revolving. Give up Bhoga. Practise renunciation, discrimination and dispassion.
Destroy the Vasanas by eradicating ignorance (Ajnana) through Brahma-Jnana, the Knowledge of the Imperishable. Then alone the wheel which binds a man to this Samsara will stop revolving. Then alone you become an Atmavan or Knower of the Self.
B.During dream the mind itself does the function of all the senses, despite the absence of the external instruments or the senses, such as eye-balls, etc. In the mind all the senses are blended.
Really it is the mind that hears, tastes, feels, etc. This proves that the real senses are within. The eye-balls, tongue, external ears, nose, hands, legs, etc., are mere instruments (Karanas).
C.During praise and pleasure, the mind expands. During censure and pain it contracts.
Mind is miniature-Maya.The causal body (Karanasarira) of the individual soul and of Isvara is one and the same.The Antahkarana or the internal organ takes four forms, viz., mind, intellect, ego and subconscious mind (Chitta). Ahamkara or the ego has connection with the intellect (Buddhi). Their abode is theVijnanamaya Kosa. Mind (Manas) has connection with the Chitta. Their abode is the Manomaya Kosa.The light of Surya (sun) brightens the intellect. The heat of Surya gives heat to Prana and thus maintains the heat of the body.
D.Above the mind is the Buddhi. The Buddhi or intellect is made up of Agni-Tattva (fire-principle). Below the mind is Prana which is also made up of fire. Between fire (intellect above) and fire (Prana below) is the mind (water). The presiding deity of the mind is moon (Chandra). Dry up this mind (water) through the fire of Vichara (intellect), or the fire of Prana (Pranayama), or both. You will attain eternal peace, everlasting bliss.
E.It is the Vritti or thought-wave that gives pain but not the objects.
Reference & Courtesy: Vedanta for beginners- Shri.Swami Sivananda