What is the ruling on one who swears falsely by the Qur’an out of fear of their family, and what is the expiation for that?

It is known that lying is forbidden (haram). If one swears by the Holy Qur’an while lying, its prohibition and punishment become more severe. This is known as the "perjurious oath" (al-yamin al-ghamūs), which is considered one of the major sins. Its expiation is through seeking forgiveness (istighfar) and repentance (tawbah). Some scholars hold the view that the expiation for an oath (kaffarat al-yamin) is also required in this case: freeing a slave, or feeding ten needy persons, or clothing them; and if one is unable, then fasting for three days. Lying is permissible if it is to avert a real harm that cannot be averted except through it, provided that it does not result in injustice or harm to another person.