Mat 5:33 ESV - "Again you have heard that it was said to those of old, 'You shall not swear falsely, but shall perform to the Lord what you have sworn.'

Mat 5:34 ESV - But I say to you, Do not take an oath at all, either by heaven, for it is the throne of God,

Mat 5:35 ESV - or by the earth, for it is his footstool, or by Jerusalem, for it is the city of the great King.

Mat 5:36 ESV - And do not take an oath by your head, for you cannot make one hair white or black.

Mat 5:37 ESV - Let what you say be simply 'Yes' or 'No'; anything more than this comes from evil.