Once, Sage Agastya had organised a grand yagya in which he had invited all the deities and sages. Lord Vishnu, Lord Brahma and Lord Shiva also went there. Agastya was puzzled as to who was the most superior among all three of them. He asked Lord Shiva in this regard. Lord Shiva replied–One who is worshipped by performing oblation- One who is the source of this universe and into whom it ultimately merges; is none other than Lord Janardhan. So he should be worshipped first of all.
He is the only one who expresses himself in three forms–Brahma, Vishnu, Mahesh. Rajas guna is predominant in lord Brahma along with some quantities of Satva guna and Tamoguna.Lord Brahma has manifested from the naval of Lord Vishnu. Tamas guna is the dominant quality in me (Rudra) with little bit of satva and rajo gunas. Narayan is the embodiment of pure satva guna. In Satya Yuga, He is worshipped by the means of meditation. During Treta Yuga, He is worshipped by the means of oblation. During Dwapar Yuga, He is pleased by nothing but the rituals of Pancharatra. During Kali Yuga, people will worship Him by various means. Lord Shiva’s revelations had completely satisfied Sage Agastya.