1. Why Krsna is called the reservoir of all pleasure

    Whatever is attractive within the cosmic manifestation is due to Krsna. Krsna is therefore the reservoir of all pleasure. The active principle of everything is Krsna, and highly elevated transcendentalists see everything in connection with Him. In the Caitanya-caritamrta it is stated that a maha-bhagavata, or highly advanced devotee, sees Krsna as the active principle in all moving and nonmoving living entities. Therefore he sees everything within this cosmic manifestation in relation to Krsna. For the fortunate person who has taken shelter of Krsna as everything, liberation is already there. He is no longer in the material world. This is confirmed in the Bhagavad-gita: Whoever is engaged in the devotional service of Krsna is already on the brahma-bhuta, [SB 4.30.20] or spiritual, platform. The very name Krsna suggests piety and liberation. Anyone who takes shelter of the lotus feet of Krsna enters the boat for crossing over the ocean of nescience. For him, this vast expanse of the material manifestation becomes as insignificant as the water in a calf's hoofprint. Krsna is the shelter of all great souls, and He is also the shelter of the material worlds. For one who is on the platform of Krsna consciousness, Vaikuntha, or the spiritual world, is not far away. He does not live within the material world, where there is danger at every step.

    From Srila Prabhupada's Krsna book ch. 14: Prayers Offered by Lord Brahma to Lord Krsna