Does a divorce occur with the words, "By divorce, you will not enter any hairdresser whatsoever," if the wife violates this, knowing that she has not yet entered one? And if it does occur, must she be taken back by intercourse before the 'iddah expires, and is expiation required?

The majority of scholars hold that a divorce oath (halaf bi al-talaq) results in divorce if the condition for which the oath was made occurs, contrary to Ibn Taymiyyah, who holds that it necessitates an expiation for an oath (kaffarat yameen) if divorce was not intended. The reference for determining what the oath was conditioned upon is the intention of the one who swore the oath. So, if he intended to prevent his wife from going to a hairdresser generally, or to prevent a foreign man from styling her hair, and he broke his oath, then divorce occurs. If the divorce occurs before consummation or valid seclusion (khalwah sahihah), the wife is irrevocably divorced (tabeen) and is not required to observe an iddah (waiting period). Her return would necessitate a new marriage contract. If it occurs after a valid seclusion, then the husband has the right to take her back (rajah) before the iddah expires. It is advisable to present the matter to a Sharia court or to trusted scholars.