“Above all, my brothers and sisters, do not swear—not by heaven or by earth or by anything else. All you need to say is a simple ‘Yes’ or ‘No.’ Otherwise you will be condemned.” (James 5:12 TNIV)
"...James and Jesus teach is that if we promise to do something and have it within our power to carry it out, then we are to do it, period. End of discussion. Become known as somebody so trustworthy that you don’t even need to shake hands, much less sign a contract. People know you’re a person of your word. And it’s striking how strongly they phrase the alternative: In James: “otherwise you will be condemned.” In Matthew: “anything beyond this comes from the evil one.” Ouch!"
Craig Blomberg
Are You a Person of Your Word?
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