As you are all sincere devotees, I am sure you are feeling the great assistance of Krishna through your activities, and the more you serve the more you will know how you are making progress in Krishna Consciousness. The same example has to be repeated how when a hungry man is given foodstuffs to eat, automatically he feels three kinds of symptoms: satisfaction of hunger, strength and pleasure. So this Krishna Consciousness Movement is based on sincere service to the Lord. We shall always remember this, and then success is assured.
Letter to Yamuna and Gurudasa, 15 July, 1969