Study of the Upanishads and Shastras (spiritual sciences) and reciting God's names may be good acts in themselves. But, if there is no love, which is the basis of all sadhana (spiritual discipline), they are of no use. They are like buttermilk. But the love of God is like well-boiled milk; it contains all the proteins and vitamins. Love reinforces one's physical, mental and spiritual energies. Devotional acts without love are like diluted buttermilk in which there are no nutrients. Dhyana (meditation) and japa (repetition of the holy name) without love are lifeless rituals. Love which expresses itself in service to all living things is the best expression of the love of God. There is no true devotion without such love. It is love which is unchanging and which does not mind any sacrifice in serving others. (Divine Discourse, Feb 5, 1984)