Is this relationship brotherhood for the sake of Allaah or a relationship that is not acceptable according to sharee’ah?

Is it permissible for her sister’s husband to stay overnight with them in their house?

She is in love with a married man and cannot keep away from him

He does not pray and he lives with his girlfriend; he wants to repent and marry her

He is in love with a girl and wants to marry her

Female student speaking with her male teacher in the university

He has repented from a haraam relationship; should he marry his former girlfriend if she becomes Muslim?

Internet relationships

Religious Man Tempted by Women

Diagnostic imaging of women by men and its relationship to fasting and touching