Matthew 5:33-35

33“Again, you have heard that it was said to the men of old, ‘You shall not make false vows, but you shall fulfill your vows to the Lord [as a religious duty].’

34But I say to you, do not make an oath at all, either by heaven, for it is the throne of God;

35or by the earth, for it is the footstool of His feet; or by Jerusalem, for it is the city of the Great King.