Sanskrit: मासो वै प्रजापतिस्तस्य कृष्णपक्ष एव रयिः शुक्लः प्रणस्तस्मादेतऋषयः शुक्ल इष्टं कुर्वन्तीतर इतरस्मिन्  
English:  12  The month, verily, is Prajapati. Its dark half, verily, is food, rayi; its bright half, the eater, prana. Therefore some rishis perform sacrifice in the bright half, some in the other half. 