Vaishnava Samhita: Nimbarka Charitam. Vol II Book V Chp 1 Shlokas 8 - 10
ज्ञानयोगात् कर्मयोगाद्भक्तियोगः परः स्मृतः
कृष्णभक्तिं विना लोके किं ज्ञानेन च कर्मणा
धर्मज्ञः कुंभकर्णश्च तत्ववेत्ता च माल्यवान्
तावुभौ न सुखं प्राप्तौ श्रीपतेर्भजनं विना
किन्तु वल्लवसुन्दर्यः प्रेमलीलारसोन्मदाः
उल्लङ्घितकुलाचाराः प्रेष्ठं प्रापुर्यदूत्तमम्
Bhakti Yoga is supreme over Karma Yoga and Gnana Yoga. What is the use of karma or gnana devoid of devotion to Lord Krishna? Kumbhakarna who knew righteous path and Malyavan who had deep knowledge of the secret precepts did not cultivate devotion to Shri Rama, the Lord of Sita. Thus they failed to achieve happiness. On the contrary, the Gopis violated dharma(of mundane conduct). Yet, they were intoxicated with the nectar of prema bhakti and hence they attained the coveted darshan of Shri Krishna.
Please check these: Excerpts from a discourse by our Sri Sri Muralidhara Swamiji
Which path do you follow?...................What is the greatness of Bhakthi?
What is the greatness of Bhakthi?
Bhakti Yoga indeed is the law of this age
Bhakti Yoga is an easy path - Sri Ramakrishna
Complete surrender is another name for jnana or liberation
Continuously remembering one's true nature is what is called Bhakthi
Chant the Mahamantra Nama kirtan :
Hare Rama Hare Rama Rama Rama Hare Hare
Hare Krishna Hare Krishna Krishna Krishna Hare Hare