bhakti

 It isn't any and every kind of bhakti that enables one to realize God. One cannot realize God without prema-bhakti. Another name for prema-bhakti is raga-bhakti. (Supreme love, which makes one attached only to God.) God cannot be realized without love and longing. Unless one has learnt to love God, one cannot realize Him. 

"But some acquire raga-bhakti directly. It is innate in them. They have it from their very childhood. Even at an early age they weep for God. An instance of such bhakti is to be found in Prahlada.

~Sri Ramakrishna