From The Laws of Manu:
7. He who can be perceived by the internal organ (alone), who is subtile, indiscernible, and eternal, who contains all created beings and is inconceivable, shone forth of his own (will).
8. He, desiring to produce beings of many kinds from his own body, first with a thought created the waters, and placed his seed in them.
9. That (seed) became a golden egg, in brilliancy equal to the sun; in that (egg) he himself was born as Brahman, the progenitor of the whole world.
10. The waters are called narah, (for) the waters are, indeed, the offspring of Nara; as they were his first residence (ayana), he thence is named Narayana.
152. Physicians, temple-priests, sellers of meat, and those who subsist by shop-keeping must be avoided at sacrifices offered to the gods and to the manes.
159. He who wrangles or goes to law with his father, the keeper of a gambling-house, a drunkard, he who is afflicted with a disease (in punishment of former) crimes, he who is accused of a mortal sin, a hypocrite, a seller of substances used for flavouring food,
167. A Brahmana who knows (the sacred law) should shun at (sacrifices) both (to the gods and to the manes) these lowest of twice-born men, whose conduct is reprehensible, and who are unworthy (to sit) in the company (at a repast).