for a restriction, whether that evidence is an explicit wording or a contextual indication.

Suppose a person authorises another to buy a car. The agent purchases a red car, whereupon the principal objects, saying, “I wanted a white one.” The principal is nonetheless bound by the red car the agent bought, because the agency was given in absolute terms and therefore remains unrestricted.

Modes of restriction

1. Restriction by explicit wording: this is a verbal expression that specifies the limitation, as when the principal says to his agent, “Sell the goods for dollars.”
2. Restriction by indication: the non-verbal indicator may be customary usage or the circumstances of the case. For example, if a student of the religious sciences appoints another to buy books for him and the agent buys engineering books, the purchase does not bind the principal, because the circumstances make it clear that the principal meant books on the religious sciences.

Fourth Maxim: “Establishing a new meaning is preferable to mere emphasis.”

Lexically, ta’sīs (establishing) derives from the root meaning “to lay a foundation,” whereas ta’kīd means “to reinforce.” Technically, when a statement can either introduce a new meaning or simply reinforce a previous one, it should be construed as introducing the new meaning, for ta’sīs contributes something not already contained in the earlier words, whereas ta’kīd merely restates the same meaning.

Thus, if someone swears that he will not do a certain act, then swears again that he will never do it, and later does it, the ruling depends on his intention. If with the second oath he intended only to reinforce the first, a single expiation is due; but if he intended a separate oath, two expiations are required.

Fifth Maxim: “When the original obligation cannot be fulfilled, one turns to its substitute.”

Here, the ‘original’ refers to what must be performed, and ‘performance’ means carrying out that original duty, whereas