1. Bhakti means voluntary cooperation with Krsna

    We are persons, and Krishna is a Person, and our relationship with Krishna He leaves open as a voluntary agreement always, and that voluntary attitude — Yes, Krishna, I shall gladly co-operate whatever you say — that ready willingness to obey is only possible if there is love. Forcing will not make me agree. But if there is love, oh, I shall gladly do it. That is bhakti, that is Krishna Consciousness.

    Srila Prabhupada; letter to Rupa Vilasa  —  Hyderabad 18 November, 1972