Scriptures say there is only one path to God-realization. And that path is bhakti. There are other complementary paths, sure. But you still need bhakti. You need to blend bhakti into the alternative paths. Without bhakti, the other paths by themselves won't help you to attain God. So bhakti is essential for God-realization.
You can extract oil from sand perhaps; maybe, you can even extract butter from water; but you cannot reach God without bhakti -- this is an irreversible fact. In Dwapar Yuga, Krishna had a friend called Uddhav. The latter believed God is formless and Brahmanand is highest. Krishna decided to bring Uddhav into bhakti marg, to set an example for the rest of the mankind.
The Lord played a trick. He requested Uddhav to do him a favor, go to Braj in Vrindavan, just 12 km away, and convey to His dear gopis a message. "Hey Uddhav, the gopis have got attached to me so much they are experiencing grief in my absence. So much so, some of them may even commit suicide. So, oh gyaani, please give them gyaan.
Tell them you are the God." Uddhav agreed to do the favor, provided Sri Krishna offered a message to his mother Yasoda. So Krishna requested him to convey this message "Dear Mother, pranaam. Please accept my obeisance. In Mathura, there is no shortage of anything.
There's opulence, lovely clothes, great food, everything... But I'm not enjoying Mathura as much as I used to enjoy Vrindavan. Here, in Mathura, there's no motherly love that I had in Vrindavan, and no motherly scolding either." Upon reaching Vrindavan, Uddhav asks for guidance to reach Nand Baba's house.
The locals ask him to watch out for streams flowing out of houses, and the house from where the largest, longest stream emanates, is the one belonging to Nand Baba. Uddhav discovers these are streams of tears rolling out of people's eyes that are unable to cope with separation or distance from Lord Krishna, their dear son, (or friend or beloved or neighbor).
Uddhav preaches to the seemingly grief-stricken gopis that he is God, that each gopi is God herself. The gopis start smiling and counter-question Uddhav that if everyone is God, then what is he preaching and why? Is God preaching to God? They tell him they are not crying for Lord Krishna as he is still amidst them.
Uddhav is puzzled and seeks to know where. So each gopi points to some place, a treetop here, or a bush there, or a pasture here, and says there He is, the Lord. Uddhav replies he is unable to see Him. Thereupon, gopis tell him they can clearly see Him.
They request Uddhav to convey to Sri Krishna that they are all happy and well. But Uddhav interjects, saying if he were to convey the message, Sri Krishna might misconstrue that gopis have forgotten Him. So the gopis say, "Do not say anything at all. Just remain silent if He enquires about us." Again Uddhav doubts if such a message would not be misunderstood to mean something terrible (like gopis committing suicide, pining for Sri Krishna) had happened.
At this stage, Radha Rani intervenes to request Uddhav to convey any message whatsoever, the only condition being that whatever his message, the smile on Lord Krishna's lips shouldn't shrink. Uddhav finally realizes that these gopis have infinite bhakti or divine love for Sri Krishna that all they care about is their Beloved's happiness, not their own bliss or travails.
They wouldn't mind the pangs of separation and the intense pathos; they are willing to endure any pain or difficulty as long as they realize their goal -- which is to ensure their Beloved remains happy every moment. This spirit typifies the Madhurya Bhaav.
He recognizes that if one becomes God-realized, one attains divine love, which helps one to stay in touch with God at all times, irrespective of the physical distance, because the God resides in such a devotee's heart and mind at all times.
Uddhav recognizes the power and bliss of bhakti and the divinity of it all. After going back to Mathura, he requests Krishna to grant him a boon that in his next birth, he is born as a blade of grass on which the gopis, the divine souls, move about.
He aspires to be in touch with the holy dust trampled by the blessed gopis. This episode proves that the biggest gyaanis forsook gyaan for bhakti.