Philo The Special Laws 2.5
4 And these men also deserve to be praised who, when they are compelled to swear, by their slowness, and delay, and evasion, cause fear not only to those who see them, but to those also who invite them to take an oath; for when they do pronounce the oath they are accustomed to say only thus much, "By the--;" or, "No, by the--;" without any further addition, giving an emphasis to these words by the mutilation of the usual form, but without uttering the express oath. 5 However, if a man must swear and is so inclined, let him add, if he pleases, not indeed the highest name of all, and the most important cause of all things, but the earth, the sun, the stars, the heaven, the universal world; for these things are all most worthy of being named, and are more ancient than our own birth, and, moreover, they never grow old, lasting for ever and ever, in accordance with the will of their Creator.
34 But I say to you, do not take oaths at all—not by heaven, because it is the throne of God, 35 not by earth because it is his footstool, and not by Jerusalem, because it is the city of the great King. 36 Do not take an oath by your head because you are not able to make one hair white or black. 37 Let your word be ‘Yes, yes’ or ‘No, no.’ More than this is from the evil one. 38 “You have heard that it was said, ‘An eye for an eye and a tooth for a tooth.’ 39 But I say to you, do not resist the evildoer. But whoever strikes you on the right cheek, turn the other to him as well.
Notes and References
"... “Yes, Yes and No, No” is found in oath formulas in later rabbinic texts, for instance by the Amorean teacher, Raba: “Let your nay and yea be both righteous.” An early, disputed text in 2 En. 49,1–2 could be a contemporary witness to this formula, or is one of the earliest interpretations of Matt 5,37. b. Much speaks in favour of a predicative understanding of the saying. The translation would then be: “Let your Yes be a Yes and your No be a No” or “Let your word be a Yes, Yes, No, No”. The message is about absolute truthfulness, an absolute reliability of the words, without compromise on speaking the truth. The Church Fathers understood the text along these lines, and Jewish sources support this view. Rabbi Huna’s saying, “the Yes of the righteous is Yes, and the No is No”, shows a similar emphasis on truthfulness in speech: Your Yes is a Yes! This saying argues, like Jewish and Hellenistic texts, that the true words make oaths superfluous. Philo criticizes people who “are in the habit of saying [yes, by the; no, by the] and add nothing more, and by thus breaking off suggest the clear sense of an oath without actually making it”. This interpretation presupposes that some words must be added to the text, e.g. an article before Yes and No, exactly like Jas 5,12; 2 Cor 1,17 and Justin’s 1 Apology 16. That in fact comes close to an oath, and is in the end an overstatement: it is difficult to imagine that people are saying continuously just yes and no! ..."
Baasland, Ernst Parables and Rhetoric in the Sermon on the Mount: New Approaches to a Classical Text (pp. 225-226) Mohr Siebeck, 2015
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