speculation / mental speculation

The definition of a pure devotee, as given by Rupa Gosvami in Bhakti-rasamrta-sindhu, can be summarized thus: his service is favorable and is always in relation to Krsna. In order to keep the purity of such Krsna conscious activities, one must be freed from all material desires and philosophical speculation. Any desire except for the service of the Lord is called material desire. And philosophical speculation refers to the sort of speculation which ultimately arrives at a conclusion of voidism or impersonalism. This conclusion is useless for a Krsna conscious person. Only rarely by philosophical speculation can one reach the conclusion of worshiping Vasudeva, Krsna. This is confirmed in the Bhagavad-gita itself. The ultimate end of philosophical speculation, then, must be Krsna, with the understanding that Krsna is everything, the cause of all causes, and that one should therefore surrender unto Him. If this ultimate goal is reached, then philosophical advancement is favorable, but if the conclusion of philosophical speculation is voidism or impersonalism, that is not bhakti.    (More...)

Srila Rupa Gosvami mourns in this connection for persons who are in the fire of false renunciation, the dry speculative habit, and who neglect devotional service. Persons who are attached to the ritualistic ceremonies recommended in the Vedas and to the impersonal Brahman cannot relish the transcendental pleasure of devotional service. Sri Rupa Gosvami advises, therefore, that devotees who have already tasted the nectar of devotion should be very careful to protect devotional service from such dry speculators, formal ritualistic elevationists and impersonal salvationists. Devotees should protect their valuable jewel of spiritual love from the clutches of thieves and burglars. In other words, a pure devotee should not describe devotional service and its different analytical aspects to dry speculators and false renouncers.    (More...)

Those who are not devotees can never achieve the benefits of devotional service. For them the subject of devotional service is always very difficult to understand. Only persons who have dedicated their lives unto the lotus feet of the Supreme Personality of Godhead can relish the real nectar of devotion.    (More...)