Taking Bhakti Scientifically - Prabhupada 0247
661007 - Lecture BG 07.15-18 - New York
Rūpa Gosvāmī says that, "A show of devotion, a show of spirituality, without reference to the Vedic knowledge, śruti, smṛti, and corollaries to the Vedas," pañcarātra-vidhim, "and the definition of bhakti-sūtras like Nārada-bhakti-sūtra and such authoritative books," aikāntikī harer bhaktiḥ, "if a man is showing himself that he is very great devotee and a man in knowledge, without any reference of the authoritative śāstra, books—oh, that is simply disturbance," utpāta. Utpāta means disturbance. A man showing that he is a great devotee, he's great man of knowledge, but he has no reference with the books of knowledge, or the authoritative books, oh, that is simply creating disturbance. That is not religiosity, neither devotion, nothing else.
So this Kṛṣṇa consciousness is a science. You have to take it scientifically, as they are described in the authoritative books, and test it by your reason and argument and knowledge, and follow it. It is science. It is not sentiment."