THUS SPAKE SWAMI SIVANANDA
Sankirtan brings darshan of God, or attainment of divine consciousness, in this Kali yuga. Sankirtan develops love. Sankirtan is the easiest, surest, safest, quickest way to attain God consciousness. Those who do sankirtan in the beginning for the sake of mental enjoyment will realize the purifying effects of sankirtan after some time and then they will themselves do it with bhava (intense feeling) and shraddha (faith). There is a mysterious power in the name of the Lord. Man cannot live on bread alone, but he can live on the name of the Lord.
The harmonious vibrations produced by the singing of the names of the Lord help the devotee to control the mind easily. They produce a benign influence on the mind. They elevate the mind at once from its old ruts or grooves to magnanimous heights of divine splendour and glory. If one does sankirtan from the bottom of one's heart with full bhava and prem (divine love), even the trees, birds and animals will be deeply influenced. They will respond. Such is the powerful influence of sankirtan. Rishis and siddhas visit the place where sankirtan is held. You can see brilliant lights all round the pandal where it is held.
The mind is purified by constant sankirtan. It is filled with good and pure thoughts. Daily sankirtan strengthens the good samskaras. The mind of a person who trains himself to think good, holy thoughts develops a tendency to think good thoughts. His character is moulded and transformed by continuous good thoughts. When the mind thinks of the image of God during sankirtan, the mental substance actually transforms into the form of the image of God. The impression of the object is left in the mind. This is a samskara. When the act is repeated very often, the samskara gains strength by repetition and a tendency or habit is formed in the mind. One who entertains thoughts of divinity actually becomes transformed into the divinity by constant thinking and meditation. The bhava and disposition is purified and divinized. The meditator and the meditated, the worshipper and the worshipped, the thinker and the thought, become one and the same. This is samadhi. This is the fruit of sankirtan.