Mishnah Bekhorot 4

¹For how long is an Israelite bound to take care of a first born? In the case of small cattle, for thirty days, and large cattle, fifty days. Rabbi Yose says: in the case of small cattle, three months. If the priest says [to the Israelite] during this period “Give it to me,” he must not give it to him. But if the first born was blemished and the priest said to him “Give it to me so that I may eat it,” then it is allowed. And in Temple times, if [the first born] was in an unblemished state and the priest said to him “Give it to me, and I will offer it up it was allowed.” A first born is eaten year by year both in an unblemished as well as in a blemished state, for it is said: “You shall eat it before the Lord your God year by year” (Deuteronomy 15:20). ²If a blemish appeared on it in its first year, he is permitted to keep it all the twelve months. If after the twelve months, however, he is not permitted to keep it except for thirty days. ³If one slaughtered the first born and then showed its blemish [to an expert]:Rabbi Judah permits, But Rabbi Meir says: since it was not slaughtered by the instructions of the expert, it is forbidden. ⁴If one who is not an expert sees a first born and it was slaughtered by his instructions, in such a case it shall be buried and he shall make reparation from his own pocket. If a [non-expert] judge gave a judgment and declared innocent a person who was really liable or made liable a person who was really innocent, declared unclean a thing which was clean or declared clean a thing which was really unclean, his decision stands but he has to make reparation from his own pocket. If the judge was an expert [sanctioned by the] court, he is exempt from making reparation. It happened once that a cow's womb was removed and Rabbi Tarfon gave it [the cow] to the dogs to eat. The matter came before the sages at Yavneh and they permitted the animal. Todos the physician said: no cow or pig leaves Alexandria of Egypt before its womb is removed in order that it may not breed. Rabbi Tarfon said: “There goes your donkey, Tarfon.” Rabbi Akiva said to him: you are exempt, for you are an expert and whoever is an expert sanctioned by the court is exempt from reparation. ⁵If one takes payment for seeing first borns, they must not be slaughtered by his instructions unless he was an expert like Ila in Yavneh whom the sages permitted to accept four isars for small cattle and six as for large cattle, whether unblemished or blemished. ⁶If one takes payment to act as a judge, his judgments are void; to give evidence, his evidence is void; to sprinkle or to sanctify, the waters are considered cave waters and the ashes are considered burned ashes. If he was a priest and he was made unclean regarding his terumah, he must give him food and drink and rub him with oil. And if he was an old sage, he mounts him on a donkey. He also pays him as he would a workman. ⁷If one is suspected in connection with first borns, one must not buy from him even deer's flesh or unprocessed hides. Rabbi Eliezer says: one may buy from him female hides we may buy from him. One may not buy from him washed or dirty wool, but one may buy spun wool or garments. ⁸If one is suspected of [ignoring the] sabbatical year, one may not buy from him flax, even combed; but spun or woven flax may be bought from him. ⁹If one is suspected of selling terumah as hullin, one may not buy even water and salt from him, the words of Rabbi Judah. Rabbi Shimon says: [one may not buy from him] whatever is connected to terumah and tithes. ¹⁰One who is suspected of ignoring the sabbatical year is not suspected of ignoring [also] the tithes. One who is suspected of ignoring tithes is not suspected of ignoring [also] the sabbatical year. One who is suspected of ignoring both is suspected of ignoring the rules of purity. And it is possible for one to be suspected of ignoring the rules of purity and yet not be suspected of ignoring the two laws [cited above]. This is the general rule: one who is suspected of [transgressing] something must not give judgment on it or testify concerning it.