36 And do not swear by your head, for you cannot make even one hair white or black. 37 Simply let your 'Yes' be 'Yes,' and your 'No,' 'No'; anything beyond this comes from the evil one.
Matthew 5:36-46 "And do not swear by your head, for you c..." NIV - Online Bible Study
It makes me wonder about things, when people swear on a book that warns against swearing oaths.
Makes me wonder what would happen if a person refused to be sworn in as president.
I read that in court, one can opt out of swearing an oath, by making some other promise, which, from what I read, was due to Quakers not wanting to take oaths due to the implication that that it would mean that they didn't tell the truth the rest of the time.