There are a number of philosophical differences between Gaudiya Vaishnava theology and that of other Vaishnava groups, although from a general perspective their core beliefs are virtually identical. The main points of difference are:
Krishna is seen as the original form of God, the source of Vishnu and not His avatar.
This teaching - shared by Nimbarka and Vallabha sampradayas and opposed by Ramanuja and Madhva - is based most prominently on Bhagavata Purana 1.3.28 (krsnas tu bhagavan svayam), the most important Purana for Gaudiya Vaishnavas, and elaborated on by Jiva Gosvami (one of Six Gosvamis of Vrindavan) in his Krishna sandarbha.
Sri Radha is the adi Shakti of Krishna, the source of all other shaktis including Lakshmi Devi and Durga Devi.
Sri Chaitanya Mahaprabhu is the latest incarnation of Krishna to descend in this yuga (age). (Kalki comes in the yuga sandhya at its end.)
Gaudiya Vaishnava Theology is prominently expounded by Jiva Gosvami in his Sat-sandarbhas, six elaborate treatises on various aspects of God. Other prominent Gaudiya Vaishnava theologians are his uncles, Rupa Gosvami and Sanatana Gosvami, Visvanatha Chakravarti and Baladeva Vidyabhushana, author of Govinda Bhashya, a famous commentary on Vedanta Sutra.
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