One who said: “I vow my weight,” he must pay his weight, in silver [if he had said in] silver, or in gold [if he had said in] gold. It happened with the mother of Yirmatia, who said, “I vow my daughter's weight.” She went up to Jerusalem and weighed her and then paid her weight in gold. [If a man said: “I vow] the weight of my hand,” Rabbi Judah says: let him fill a barrel with water and put it [his hand] in up to the elbow. Then let him weigh the flesh, bones and sinews of a donkey and put it into the barrel until it is filled up again. Rabbi Yose said: “But how is it possible to account exactly one kind of flesh against another kind of flesh, and one kind of bones against another kind of bones? Rather: one estimates what the hand is likely to weigh.