Matthew 5.33-36 gives us the dominical saying:
33 "Again, you have heard that the ancients were told, 'You shall not make false vows, but shall fulfill your vows to the Lord.' 34 "But I say to you, do not swear [ὀμόσαι] at all, either by heaven, for it is the throne of God, 35 or by the earth, for it is the footstool of His feet, or by Jerusalem, for it is the city of the great King. 36 Nor shall you swear [ὀμόσῃς] by your head, for you cannot make one hair white or black."
Mark uses the verb ὄμνυμι only twice. The first time is in Mark 6.23:
23 And [Herod] swore [ὤμοσεν] to her, "Whatever you ask of me, I will give it to you; up to half of my kingdom."
The second time is in Mark 14.71:
71 But [Peter] began to curse and swear [ὀμνύναι], "I do not know this man you are talking about!
Both of these are, in context, unwise instances of swearing. Was Mark aware of a saying (dominical or otherwise) against swearing or making oaths, and did he decide to illustrate the principle in stories rather than to simply place it on the lips of Jesus? Or did Matthew take the principle from Marcan storytelling and turn it into a dominical saying? Or are there other, more likely options? What is the relationship, if any, between these verses?
Ben.