Is intention required for the exception (Istithna) to be valid?
General Chapter
Al-Mughni
Book of Oaths
Primary text
The judge (Al-Qadi) stipulated that the exception requires intention. If someone intended to affirm the oath but the exception escaped his tongue unintentionally, or if the exception is a frequent habit and slipped out without intent, it is invalid. This is because just as the oath is not established without intent, so too is the exception.
Supporting text
Some scholars mentioned that the exception is only valid if intended concurrently with the beginning of the oath. If someone swears without intending the exception, and then offers the exception after finishing the oath, it is ineffective. This is because such a condition contradicts the general meaning of the Hadith, which states: "Whoever swears, then says, 'If Allah wills,' he will not break his oath." Furthermore, the utterance of the exception must immediately follow the oath, and so must its intention.