Matthew 5:33-37 - The Sermon On The Mount: Taking Oaths
33 "Again, you have heard what was said to people in time's past [Lev. 19:12], 'You must not go back on your oaths, but [rather] fulfill the oaths you take to the Lord.' 34 But I say to you, do not take any oath, [saying] 'by heaven,' for it is God's throne; 35 nor 'by earth,' for it is the footstool for His feet; nor 'by Jerusalem,' for it is the city of the great King [i.e., God]. 36 You should not take an oath, [saying] 'by my head,' for you cannot make a single hair white or black. 37 But you should just say 'yes' [when you mean] yes, and 'no' [when you mean] no. Whatever you say beyond these [i.e., enforcing them by oaths] is of the evil one [i.e., the devil].