Matthew 5:33-37

33 "You have heard that it was said to your ancestors, 'Never break your oath, but give to the Lord what you swore in an oath to give him.'

34 But I tell you don't swear an oath at all. Don't swear an oath by heaven, which is God's throne,

35 or by the earth, which is his footstool, or by Jerusalem, which is the city of the great King.

36 And don't swear an oath by your head. After all, you cannot make one hair black or white.

37 Simply say yes or no. Anything more than that comes from the evil one.