Jesus continues His authoritative interpretation of God’s moral law by forbidding all unreliable and unnecessary speech. First, he counters the current silly practice of swearing an oath by heaven or earth, Jerusalem, or even one’s head – all in an effort to avoid using God’s name in vain (5:34-36) or promising to give something to God, and then not fulfilling that obligation (see Leviticus 19:12; Numbers 30:2; Deuteronomy 23:21,23). Our Lord goes further than that, however. He also forbids all frivolous oaths; then all superfluous ones. “Let your ‘Yes’ be ‘Yes.’” That is enough. Some Christians believe that Jesus here prohibits us from taking an oath in court, or even making a marriage vow, but most interpreters think that Jesus means only to emphasize the necessity of saying only what we mean and know to be true. Our words should be trustworthy. When we sign the tax return, it should be fair and accurate. When we endorse a check, there should be money in the bank. When we put our name to a credit card bill, we should be able to pay it. When we promise to do something, we should fulfill our promise. Our commitments should come from a sober sense of what we can actually perform. That includes marriage vows, which are solemn pledges made before God in the presence of human witnesses. In fact, it encompasses all our speech: Everything we say should be fully accurate and trustworthy. No more, no less. May God give us grace to avoid making commitments that we cannot keep, and to speak only what we know to be true!