Lord Caitanya's greatest gift was His teaching that Kṛṣṇa can be treated as one's lover. In this relationship the Lord becomes so much attached to His devotee that He expresses His inability to reciprocate. Kṛṣṇa was so obliged to the gopīs, the cowherd girls of Vṛndāvana, that He felt unable to return their love. "I cannot repay your love," He told them. "I have no more assets to give." Devotional service on this highest, most excellent platform of lover and beloved, which had never been given by any previous incarnation or ācārya, was given by Caitanya Mahāprabhu. Therefore Kṛṣṇadāsa Kavirāja, quoting Śrīla Rūpa Gosvāmī, writes in the fourth verse of his book, "Lord Caitanya is Kṛṣṇa in a yellow complexion, and He is Śacīnandana, the son of mother Śacī. He is the most charitable personality because He came to deliver kṛṣṇa-prema, unalloyed love for Kṛṣṇa, to everyone. May you always keep Him in your hearts. It will be easy to understand Kṛṣṇa through Him."
We have often heard the phrase "love of Godhead." How far this love of Godhead can actually be developed can be learned from the Vaiṣṇava philosophy. Theoretical knowledge of love of God can be found in many places and in many scriptures, but what that love of Godhead actually is and how it is developed can be found in the Vaiṣṇava literatures. It is the unique and highest development of love of God that is given by Caitanya Mahāprabhu.
Even in this material world we can have a little sense of love. How is this possible? It is due to the presence of our original love of God. Whatever we find within our experience within this conditioned life is situated in the Supreme Lord, who is the ultimate source of everything. In our original relationship with the Supreme Lord there is real love, and that love is reflected pervertedly through material conditions. Our real love is continuous and unending, but because that love is reflected pervertedly in this material world, it lacks continuity and is inebriating. If we want real, transcendental love, we have to transfer our love to the supreme lovable object—Kṛṣṇa, the Supreme Personality of Godhead. This is the basic principle of Kṛṣṇa consciousness.
In material consciousness we are trying to love that which is not at all lovable. We give our love to cats and dogs, running the risk that at the time of death we may think of them and consequently take birth in a family of cats or dogs