'Swear' in the Bible

Moses took the bones of Joseph with him, for he had made the sons of Israel solemnly swear, saying, “God will surely take care of you, and you shall carry my bones from here with you.”

Remember Abraham, Isaac, and Israel, Your servants to whom You swore by Yourself, and said to them, ‘I will multiply your descendants as the stars of the heavens, and all this land of which I have spoken I will give to your descendants, and they shall inherit it forever.’”