33 Again, ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths: 34 But I say unto you, Swear not at all; neither by heaven; for it is God’s throne: 35 Nor by the earth; for it is his footstool: neither by Jerusalem; for it is the city of the great King. 36 Neither shalt thou swear by thy head, because thou canst not make one hair white or black. 37 But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil.
(Numbers 30:1-16)
Quakers have a traditional testimony of integrity that we try to live up to. One component of this testimony is speaking the truth at all times.
In swearing an oath to tell the truth, the whole truth and nothing but the truth, you are setting a dual standard for yourself. It is as if you are not obligated to tell the truth at all other times. Friends think that this is a moral hazard that they will not expose themselves to and so, refuse to swear oaths.
In legal proceedings we affirm to tell the truth. This is a hard won legal right that early Quakers went to prison for as a matter of conscience. In modern times this phrase; do you swear or affirm to tell the truth, goes by without much notice.
There is another part of modern speech that goes by without much notice. It is sarcasm, the use of language which on the face of a situation appear to be appropriate, but is meant to be understood as meaning the opposite of what is said, usually in a negative or destructive way. Sarcasm is ridicule.
Sarcasm is a close cousin to irony, but many people don’t understand, or don’t care to understand the difference. Situations can be ironic. People can be unintentionally or intentionally ironic, but sarcasm requires conscious verbal aggression.
The fact that you are not saying what you mean is enough for me to stay away from sarcasm. When you are conscious of it you will notice it’s pervasiveness in our culture.
Can you go a day without being sarcastic? A week? How about an hour…?
Roger Vincent Jasaitis 
Very interesting, Roger. Thanks for raising awareness (mine) about this. Ginger