Vedic texts state that Lord Chaitanya is the Supreme Person, Krishna, appearing as His own worshiper. He is the combined form of Krishna and Krishna's most dear devotee, Srimati Radharani. He came to experience the love She feels for Him, and to show by example how to fully surrender to Krishna.
He exhibited symptoms of love of God to the highest degree, and emphasized chanting the holy names of Krishna as the best means to attain love of God.
Srimad-Bhagavatam 1.7.13-14, purport—Lord Krishna Chaitanya is Krishna Himself in the garb of a devotee of Krishna, and therefore the versions of both Lord Krishna and Sri Krishna Chaitanya Mahaprabhu are identical.
Srimad-Bhagavatam 3.33.4, purport— Sometimes the Supreme Personality of Godhead Himself wonders how much transcendental pleasure is within Himself, and in order to taste His own potency, He sometimes takes the position of tasting Himself. Lord Chaitanya is Krishna Himself, but He appears as a devotee to taste the sweetness of the transcendental mellow in Himself which is tasted by Srimati Radharani, the greatest of all devotees.
Chaitanya Charitamrita, Adi-lila, Introduction—Lord Chaitanya Mahaprabhu should therefore not be considered one of us. He is Krishna Himself, the supreme living entity, and as such He never comes under the cloud of maya. Krishna, His expansions and even His higher devotees never fall into the clutches of illusion. Lord Chaitanya came to earth simply to preach Krishna-bhakti, love of Krishna. In other words, He is Lord Krishna Himself teaching the living entities the proper way to approach Krishna. He is like a teacher who, seeing a student doing poorly, takes up a pencil and writes, saying, “Do it like this: A, B, C.” From this one should not foolishly think that the teacher is learning his ABC’s. Similarly, although Lord Chaitanya appears in the guise of a devotee, we should not foolishly think He is an ordinary human being; we should always remember that Lord Chaitanya is Krishna (God) Himself teaching us how to become Krishna conscious, and we must study Him in that light.
Chaitanya Charitamrita, Adi-lila 1.4—May the Supreme Lord who is known as the son of Śrīmatī Śacī-devī be transcendentally situated in the innermost chambers of your heart. Resplendent with the radiance of molten gold, He has appeared in the Age of Kali by His causeless mercy to bestow what no incarnation has ever offered before: the most sublime and radiant mellow of devotional service, the mellow of conjugal love.
Chaitanya Charitamrita, Adi-lila 4.41, purport—Lord Chaitanya did not invent a system of religion, as people sometimes assume. Religious systems are meant to show the existence of God, who is then generally approached as the cosmic order-supplier. But Lord Sri Chaitanya Mahaprabhu’s transcendental mission is to distribute love of Godhead to everyone. Anyone who accepts God as the Supreme can take to the process of chanting Hare Krishna and become a lover of God. Therefore Lord Chaitanya is the most magnanimous. This munificent broadcasting of devotional service is possible only for Krishna Himself. Therefore Lord Chaitanya is Krishna.
Chaitanya Charitamrita, Introduction—In order to study Radharani, Krishna lived in Her role and tried to understand Himself. This is the secret of Lord Chaitanya’s incarnation. Chaitanya Mahaprabhu is Krishna, but He has taken the mood and role of Radharani to show us how to love Krishna.
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