Exodus 22:28-31 - Regulations Regarding Tribute And Holiness
28 "Thou shalt not rail upon the judges, neither curse the ruler of thy people.
29 Thy fruits, whether they be dry or moist, see thou keep not back. Thy firstborn son thou shalt give me: 30 likewise shalt thou do of thine oxen and of thy sheep. Seven days it shall be with the dam, and the eighth day thou shalt give it me.
31 Ye shall be holy people unto me, and therefore shall ye eat no flesh that is torn of beasts in the field. But shall cast it to dogs."