Vedic Yajnas are very elaborate.
They include Yajnas such as Chaturmasya, Pashu Bandha, Jyotishtoma, Atriratra, etc.
Every Yajna involves the participation of scholars from each branch of the Veda: Rigveda, Yajurveda, Samaveda, and Atharvaveda.
Among them, the Yajurvedic scholar is called Adhvaryu.
अध्वर्य्युः - अध्वरं यज्ञं यौति सम्पादयति
Adhvaryu is in charge of the execution of the Yajna.
The term is derived from अध्वरः (Yajna)
Adhvaryu is in charge of various responsibilities such as:
He also chants appropriate mantras from the Yajurveda while going about performing his duties.
Adhvaryu has three assistants:
Purohitas of Yajnas are collectively called Ritwiks.
The other chief Ritwiks are:
Brahma should know all the four Vedas.
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