It is narrated from a Companion (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Do not meet traders coming from outside before they reach (the market); no townsman should sell the goods of a villager; and whoever buys a goat or she-camel whose udder is tied and appears swollen, then when he milks it (and its reality becomes clear), he has the choice of two options: (either he keeps it as it is with him), or if he wishes to return it, he should also give a sa’ (measure) of wheat (or dates) along with it.