The teaching of Jesus is so clearly the way things ought to be - and yet how different is the reality of human history…
"Thou shalt not bear false witness against thy neighbor" and a few passages about the seriousness of sacred oaths (e.g., Leviticus 19:12, Numbers 30:2, and Deuteronomy 23:21) were among the strongest injunctions in the Old Testament for honesty in speech. True to form, Jesus advocates the perfected fulfillment of those principles, when, quite simply, a person's "yes" would mean "yes,"and "no" would mean "no," and there would not be any need of swearing to guarantee credibility.
No one would disagree, for in this matter especially, the teaching of Jesus is so clearly the way things ought to be - and yet how different is the reality of human history, with our own "enlightened" age being no exception! Tragically, in fact, modern times have witnessed highly publicized equivocation and prevarication even of testimony given under solemn oath.
But instead of the hazy honesty advocated and practiced by too many politicians and media spin doctors, you and I, as followers of Christ, need to strive to live by His standards of truthfulness. In large matters and small matters, it's always possible and right to witness with the splendor of the Truth, which is Christ Himself!