1 Samuel 28:10

10But Saul swore to her by the Lord, a“As the Lord lives, no punishment shall come upon you for this thing.”

1 Samuel 30:15

15And David said to him, “Will you take me down to this band?” And he said, “Swear to me by God that you will not kill me or deliver me into the hands of my master, and I will take you down to this bband.”

Hebrews 6:16

16For people swear by something greater than themselves, and in all their disputes can oath is final for confirmation.
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