Making a Promise

Let your 'yes' be 'yes'.

In the Sermon on the Mount, Jesus gives a direct command to not swear oaths at all. This includes swearing by heaven, earth, or even your own head. This goes against common phrases like 'I swear to God' or taking a formal oath in court or for public office. 'But I say to you, Do not swear at all...' — Matthew 5:34 (ESV)