Sri Krishna, God of Prema
Sri Krishna is called as the God of prema. He taught the world the act of love through the villagers of Vraja. They were willing to do anything and everything for Sri Krishna. This is the most evolved concept of God realization .
Similarly, Sri Krishna interacted with every living entity in Vrindavana, including the deer, peacocks and cows. Such loving interactions are called as bhakti yoga, sharanagati or prema bhakti. When one relates with God having no motivation other than love and without any interruption, such a relationship is very relishable, because there is no expectation other than love.
Such loving descriptions are scattered in all the vedic literatures, but especially in Bhagavatam and Ramayana. When our senses, mind, intelligence and ego are engaged in doing what they are supposed to be doing with a heart filled with love for God, then one becomes a perfect yogi.