For example, suppose a man pledges a cow and the pledgee begins milking it. We say: You may milk it in proportion to its maintenance. If the value of its milk is one hundred per week and its maintenance is one hundred per week, then in this case he neither owes anything nor is owed anything. If the milk is worth two hundred per week and the maintenance is one hundred, he must pay the pledgor one hundred; but this one hundred remains pledged, because it is part of the animal’s increase. Conversely, if the maintenance is two hundred and the milk is worth one hundred, he may recover from the pledgor the amount exceeding the value of the milk.
If someone were to ask: What is the evidence, and what is the wisdom behind this?
We say: The evidence is the saying of the Prophet, peace and blessings be upon him: “A pledged riding animal may be ridden in return for its maintenance, and the milk of a pledged dairy animal may be drunk in return for its maintenance. The one who rides and drinks is responsible for the maintenance.” (1)
If someone were to say: The apparent meaning of the hadith is that the milk is in exchange for the maintenance, and riding is in exchange for the maintenance, whether the benefit is greater or less than the maintenance?
The answer is that this is not the apparent meaning of the hadith. The hadith says, “in return for its maintenance.” The preposition bi- may either indicate compensation or causation. If we take it to indicate compensation, then it is clear that he may not take more than the maintenance. If we take it to indicate causation, the same follows, because a cause does not extend beyond the scope of its effect. Thus, it may be said that the preposition here indicates causation, and causation does not extend beyond the scope of the resulting effect. In either case, riding and milking are only permitted in proportion to the maintenance.
As for the wisdom behind this, an animal requires maintenance: it needs food, drink, shade, and warmth during winter days. If we were to say that the pledgee