The practice of employing the doctrine of takhayyur is not without restrictions. Many Muslim jurists have specified the conditions for applying this doctrine. According to Taqi al-Din al-Subki, the three valid reasons for exercising Takhayyur are: (a) when the individual perceives that the other school's viewpoint is more accurate, (b) when the individual is of the opinion that his imam is more correct or when he has no opinion but changes schools as a pious precaution, and (c) when relaxation of the regulations is required due to a need or necessity. On the other hand, unacceptable reasons for him include: (a) changing schools without a need or requirement, (b) following one's whims on a regular basis, therefore constructing one's own religious law from rukhsas, and (c) changing schools if that leads to a legal complication. Shihab al-Din al-Qarafi allowed Takhayyur under three conditions: the opinions should not be combined in a way that contradicts consensus or creates an opinion that no jurist has expressed; the jurist is trustworthy; and the specific opinion sought is not sought in order to get rukhsah (concessions).
