Śrīmad-Bhāgavatam · Text 3.12.35
Who is speaking and story frame
चातुर्होत्रं कर्मतन्त्रमुपवेदनयै: सह ।
धर्मस्य पादाश्चत्वारस्तथैवाश्रमवृत्तय: ॥ ३५ ॥
cātur-hotraṁ karma-tantram
upaveda-nayaiḥ saha
dharmasya pādāś catvāras
tathaivāśrama-vṛttayaḥ
The four kinds of paraphernalia for conducting the fire sacrifice became manifest: the performer [the chanter], the offerer, the fire, and the action performed in terms of the supplementary Vedas. Also the four principles of religiosity [truth, austerity, mercy and cleanliness] and the duties in the four social orders all became manifest.
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