'Oath' in the Bible

And she made an oath, and said, O Lord of armies, if you will truly take note of the sorrow of your servant, not turning away from me but keeping me in mind, and will give me a man-child, then I will give him to the Lord all the days of his life, and his hair will never be cut.

And the man Elkanah with all his family went up to make the year's offering to the Lord, and to give effect to his oath.

Therefore I swore an oath to the house of Eli, 'The sin of the house of Eli can never be forgiven by sacrifice or by grain offering.'"

and the men of Israel were worn out that day, for Saul had placed the troops under an oath: “The man who eats food before evening, before I have taken vengeance on my enemies is cursed.” So none of the troops tasted any food.

And when the people were come into the wood, behold, the honey dropped; but no man put his hand to his mouth: for the people feared the oath.

But Jonathan heard not when his father charged the people with the oath: wherefore he put forth the end of the rod that was in his hand, and dipped it in an honeycomb, and put his hand to his mouth; and his eyes were enlightened.

Then answered one of the people, and said, Thy father straitly charged the people with an oath, saying, Cursed be the man that eateth any food this day. And the people were faint.

[When night came and the oath ended] the people rushed greedily upon the spoil. They took sheep, oxen, and calves, and slaughtered them on the ground; and they ate them [raw] with the blood [still in them].

Saul listened to Jonathan’s advice and swore an oath: “As surely as the Lord lives, David will not be killed.”

David again took an oath: "Your father certainly knows that I've found favor with you, and so he told himself, "Jonathan must not know this so he won't be upset.' But as certainly as the LORD is alive and living, and as certainly as I'm alive and living, too, there is only a step between me and death."

Jonathan once again took an oath with David, because he loved him. In fact Jonathan loved him as much as he did his own life.

Jonathan said to David, "Go in peace, because we have sworn, the two of us, [an oath] in the name of Yahweh, saying, "Yahweh will be between me and you, and between my offspring and your offspring forever." Then he got up and left, and Jonathan went into the city.

So give me your oath by the Lord, that you will not put an end to my seed after me or let my name be cut off from my father's family.

David promised Saul this on oath. Then Saul went to his house, and David and his men went up to the stronghold.

But Saul swore an oath to her by the Lord, "As surely as the Lord lives, you will not incur guilt in this matter!"

And David said to him, Will you take me down to this band? And he said, If you give me your oath that you will not put me to death or give me up to my master, I will take you to them.