What is the recompense for whoever prevents young men and women from marrying, and causes them to persist in practicing masturbation, due to their efforts to seek out suitors and defame the mother’s reputation?

It is not permissible to deter a suitor from a Muslim girl by mentioning her faults and her mother's faults to turn them away from her unjustly. This constitutes harming believers, which is among the greatest prohibitions decreed by Allah the Almighty and His Messenger, peace be upon him. Allah the Almighty says: "And those who harm believing men and believing women for [something] other than what they have earned have certainly borne slander and manifest sin." and "Woe to every slanderer and backbiter."

The Messenger of Allah, peace be upon him, forbade seeking out the faults of Muslims and backbiting about them. Whoever does so, Allah will expose him in his own home.