'Vowed' in the Bible

She replied, “Please, may the king invoke the Lord your God, so that the avenger of blood will not increase the loss, and they will not eliminate my son!”“As the Lord lives,” he vowed, “not a hair of your son will fall to the ground.”

But in response, Ittai vowed to the king, “As the Lord lives and as my lord the king lives, wherever my lord the king is, whether it means life or death, your servant will be there!”