Greetings,
1 - At-Talaq al-Mudaf (Postdated Divorce) is permissible and takes effect at its specified time. Postdated divorce means that the formula of divorce is linked to a specific time, such as saying, "You are divorced after a month," and so on. Therefore, the statement made by the brother who is imprisoned to his wife, "After six months, you are divorced and you may marry," takes effect as a divorce after the time he specified for her.
2 - Separation (At-Tafreeq) due to imprisonment:
The majority of the Fuqaha (jurists) hold that separation from an imprisoned person is not permissible at all. That is, it is not permissible for a woman to petition a judge (Qadi) to separate her from her husband regardless of the duration of his imprisonment, because he is an absentee whose life is known, and his absence is due to a valid excuse—that he is imprisoned. This is the position held by the Hanafiyah, Shafi’iyah, and Hanabilah.
However, Imam Malik permits it if the wife requests it from the judge and claims harm (Darar), provided it occurs after one year of the husband's imprisonment.
We do not wish to adopt (natabanna) a specific view on this matter; the wife is free to choose to follow (taqlid) any madhhab regarding this issue.
However, I advise women to be patient. Perhaps Allah will grant their husbands a way out so they may return to their homes, and the woman, her husband, and the rest of the family may be reunited in goodness.
Through her patience, she will have a great reward, and Allah is with the patient.
وَاللَّهُ مَعَ الصَّابِرِينَ
"And Allah is with the patient." (QS. Al-Baqarah [2]: 249)
But if the wife insists on requesting separation, it is better that she requests it directly from her husband. I do not think a husband would refuse to divorce his wife if she asks for it and he knows that her remaining bound to him while he is behind bars causes her harm.
Best regards.
January 12, 2004 CE.