'Oath' in the Bible

On that day, there will be five cities in the land of Egypt that speak the {language} of Canaan and swear an oath to Yahweh of hosts. One will be called "City of the Sun."

Whoever blesses himself in the land shall bless himself by the God of trustworthiness, and the one who swears an oath in the land shall swear by the God of trustworthiness, because the former troubles are forgotten, and they are hidden from my eyes.