—even once—renders a person no longer legally upright, and thus unfit to serve as a guardian. Ibn ʿAbd al-Qawī, may Allah have mercy on him, said in his didactic poem:
It has been said that backbiting and tale-bearing are minor sins;
yet both are major sins, according to Ahmad’s explicit statement.
Accordingly, the matter is highly problematic. For this reason, some of the scholars of the school hold that legal uprightness is not a condition; rather, the condition is trustworthiness: he must be acceptable and trustworthy with regard to his daughter, and he must not approve of an unsuitable match for her. This is the correct view.
How many a man appears outwardly upright, yet, as far as his daughter is concerned, cares for nothing but money: he takes the money and marries her to the most immoral of people, without concern. In reality, such a man is unfit to serve as a guardian, for his betrayal of his daughter is incompatible with his uprightness. The sound view in this matter, therefore, is that the guardian must be entrusted with the welfare of his female ward. This is the most important condition, because he acts on behalf of someone else; thus, ensuring the interests of that other person must be taken into account. As for his own uprightness and religious commitment, that concerns himself.
You may find many fathers who are among the most immoral servants of Allah: they drink wine, commit fornication, shave their beards, smoke tobacco, engage in fraudulent dealings, backbite people, and spread tales among them. Yet when it comes to their daughters’ interests, they would never neglect them.
In al-Rawd (1), an exception to the condition of uprightness is mentioned: “Except in the case of a ruler and a master marrying off his slave woman, for uprightness is not stipulated.” If the ruler marries off a woman who has no guardian, uprightness is not stipulated, because were we to require uprightness in the ruler, this would impose hardship upon the Muslims. Thus, if we assume that the ruler