What is the ruling on pledging an oath on the Qur’an to marry a girl? Is the failure to complete the marriage considered a breach of the vow, necessitating expiation, if the girl's father refuses to marry her off? Is it permissible to be patient and not marry anyone else?

If you committed fornication with a girl, you have made a grave mistake and betrayed the trust of her father, who also erred by allowing you to be alone with his daughter. Her father has the right to refuse to marry her to you, especially if he sees a deficiency in your religiosity and character. Regarding the promise to marry her, you can retract it if her father refuses, and there is no expiation required of you if you did not swear an oath to it. However, if you did swear an oath, then you must pay the expiation for breaking an oath by feeding ten poor persons, or clothing them, or emancipating a slave, or fasting three days if you cannot find these. It is permissible for you to be patient and not marry anyone else but her, if you do not fear falling into the unlawful.