There has been lots of Spiritual masters (I'm avoiding the word Guru deliberately, because of such rampant misuse of it) who were proponents of various sects of Vaishnavam such as Madhava (Brahma-Vaishnavam Sect, ब्रह्म-वैष्णवं), Shridhara Swamy (Rudra-Vaishnavam Sect, रूद्र-वैष्णवं) etc.
What were the main identifying factors of these sects or sampradayas (सम्प्रदाय)? What differentiated these from each other and from themselves?
There are four main Vaishnava sampradayas, or chains of disciplic succession descending down through the important acharyas, or spiritual preceptors. These are also the main schools of thought in the Vedic tradition. Thus, anyone should belong or be a part of one of these sampradayas if they are going to be considered authorized in their Vedic teachings or practice. These sampradayas are the following:
Sri sampradaya, where the main exponent is Ramanujacharya (who lived in 12th century, born in 1016), propagated the doctrine called visista advaita, or oneness with varieties of the Lord and His energies. This is said to have originated from Sri or Goddess Lakshmi.
Brahma sampradaya, where the main exponent is Madhvacharya (who lived in 13th century, born in 1238), propagated the doctrine called visista dvaita, or duality with varieties. This is said to have originated from Lord Brahma.
Rudra sampradaya, the main exponent is Vishnu Swami, who propagated the doctrine called suddha dvaita, or pure transcendental duality; Vallabha Acharya is also a branch of this sampradaya. This is said to have originated from Rudra or Lord Shiva.
Hamsa, Catuhsana, Kumara or Sanat sampradaya, the main exponent is Nimbarka, who propagated the doctrine called dvaita advaita or simultaneous oneness and duality. This is said to have originated from Lord Brahma’s sons, the Kumaras or which Sanat Kumara is one.
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