An oath is like a formal version of a promise – in saying certain words, you guarantee that you are speaking the truth. Quakers claimed always to speak the truth, so they took issue with swearing oaths, seeing them as creating a double standard of truthfulness. If you need to swear an oath to guarantee you are telling the truth, then you can’t really feel that you must tell the truth the rest of the time.
I couldn't help but think of someone who recently swore an oath and who certainly would not be able to answer in the affirmative these questions, posed in the Advices and Queries:
Are you honest and truthful in all you say and do? Do you maintain strict integrity in business transactions and in your dealings with individuals and organisations? Do you use money and information entrusted to you with discretion and responsibility?
Sadly that may mean that, for many of the rest of us, the next paragraph of the Advices and Queries will become increasingly pertinent:
If pressure is brought upon you to lower your standard of integrity, are you prepared to resist it? Our responsibilities to God and our neighbour may involve us in taking unpopular stands. Do not let the desire to be sociable, or the fear of seeming peculiar, determine your decisions.