Matthew 5:34-37

but I tell you, don’t swear at all: neither by heaven, for it is the throne of God; nor by the earth, for it is the footstool of his feet; nor by Jerusalem, for it is the city of the great King. Neither shall you swear by your head, for you can’t make one hair white or black. But let your ‘Yes’ be ‘Yes’ and your ‘No’ be ‘No.’ Whatever is more than these is of the evil one.