Owing to having understood the nature of truth of which are directed all sacrifices, a certain class of men perform sacrifices by the mind (meditation), another by words (recitation of hymns) and another by actions.
यतो यज्ञाः प्रवर्धन्ते सत्यस्यैवावरोधनात्। मनसान्यस्य भवति वाचान्यस्याथ कर्मणा॥