a solemn pledge (to oneself or to another or to a deity) to do something or to behave in a certain manner
"they took vows of poverty"
A solemn promise to perform some act, or behave in a specified manner, especially a promise to live and act in accordance with the rules of a religious order.
"After years of wandering, she finally vowed to dedicate her life to serving others within the strict confines of the convent."
dedicate to a deity by a vow
"After promising his safety to the mountain god, he vowed to return every year with fresh offerings."
To make a vow; to promise.
"After losing his job, he vowed to never again neglect his family's financial needs."