Learn thou this by prostration, by investigation and by service. The wise, the seers of the essence of things, will instruct thee in wisdom. (Gita, IV-34)
Guru or a spiritual preceptor is necessary for aspirants. Some do the practice for some years, independently. Later on, they feel acutely the necessity for a Guru. They come across some obstacles on the way. They do not know how to proceed and how to obviate these impediments. Then they begin to search for a master. This particularly happens in Yogic practice.
It is the duty of the Guru to set each of his disciples upon that path of spiritual development which is best suited to the Chela, one on one path, one on another, according to the Gurus insight into the innate tendency of each.
Isvara is Guru of Gurus. He removes the veil of ignorance and blesses the ignorant Jivas (embodied Souls). The aspirant should regard his immediate Guru in the physical form as an incarnation of that Guru of Gurus and should have equal devotion to him also. Guru in the physical form is the main source and embodiment of all good and happiness that can accrue to the Chela. The disciple should realize the supreme necessity of obeying the Gurus commands and behests and keeping his faith in him unsullied and staunch. Lay bare to your Guru the secrets of your heart; and the more you do so, the greater the sympathy, which means an accession of strength to you in the struggle against sin and temptation.
Transmission of Spiritual Power
Just as you can give an orange to a man and take it back, so also spiritual power can be transmitted by one to another and taken back also. This method of transmitting spiritual power is termed Sakti-Sanchara. Like birds, fish and tortoise, the transmitting of spiritual power can be done by the Guru through touch or sight or willing, and thinking. The transmitter sometimes enters the astral body of the student and elevates his mind through his power. The operator makes the subject sit in front of him and asks him to close his eyes and then transmits his spiritual power. The subject feels the electric current actually passing from Muladhara Chakra higher up to the neck and top of the head. He does various Hatha Yogic Kriyas, Asanas, Pranayama, Bandhas, Mudras, etc., by himself without any instruction, through inspiration. Here Prakriti (Nature) works herself. The student must not restrain his Iccha-Sakti (Power of Desire). He must act according to the inner light. The mind is highly elevated. The moment the aspirant closes his eyes, meditation comes by itself. Through Sakti-Sanchara, Kundalini is awakened by the grace of the Guru in the disciple.
A spiritual teacher actually transmits his spiritual power to his disciple. A certain spiritual vibration of the Satguru is actually transferred to the mind of the disciple. Sri Ramakrishna Paramahamsa actually transmitted his spiritual power to Swami Vivekananda. Lord Jesus did the same to his disciples. This is Masters spiritual touch. A disciple of Samartha Ramdas transmitted his power to that dancing girls daughter who was very passionate towards him. The disciple gazed at her and gave her Samadhi. Her passion vanished. She became very religious and spiritual. Mukund Rai, a Maharashtra saint, put the Badshah in Samadhi.
By the Gurus Grace, the devotee attains the eight-stepped Yoga (Ashtanga Yoga); by the Grace of Lord Siva, he attains perfection in Yoga which is eternal.
Mind – Its Mysteries and Control by Sri Swami Sivananda