The World Federation One Stop Fiqh

Ruling 2659

A person who makes a vow must be of the age of legal responsibility (bāligh), and sane (ʿāqil). He must also make the vow of his own volition (ikhtiyār) and have the intention (qaṣd) to make it. Therefore, a vow is not valid if it is made by someone who has been compelled to make it, or who in his anger made it unintentionally or did not make it of his own volition.