In many questions asked inon this site, I frequently see a line about Vishnu teaching principles of Vaishnavism to his four disciples:
Vishnu is said to have taught the principles of Vaishnavism to four disciples: Lakshmi, Brahma, Shiva and Sanatkumara. And in turn they started the four main Sampradayas or traditions of Vaishnavism: Sri Sampradayam, Brahma Sampradayam, Rudra Sampradayam, and Kumara Sampradayam.
So, I want to know which scripturescriptures mention this thing? I know it's not mentioned in Valmiki Ramayana and Mahabharata of Vyasa. Neither it's mentioned in Srimad Bhagavata, Vishnu and Padma Purana as far as I'm aware.I know There is possibility that it's mentioned in other Puranas like Varaha and Narada.
Most probably it's mentioned in Pancharatra Agamas. If it's mentioned, I want to know which Samhita and Chapter of Pancharatra Agamas mention it? Also when did Lord Vishnu do this teaching?