2,664. A Flying Camel
Hilchos Shevuos 5:20
Let’s say that someone took an oath not to sleep for three days, or not to eat anything for seven days, etc. Such an oath is considered to be in vain. We don’t say that he should stay awake or fast until he’s overwhelmed by discomfort and only eat or sleep when he can’t stand it any longer. Rather, such a person is liable to lashes right away for making a vain oath and he can eat and sleep whenever he likes.
Hilchos Shevuos 5:21
Let’s say that someone took an oath that he saw a camel flying through the air. When asked why he made a vain oath, he replies that he saw a gigantic bird and that he metaphorically referred to it as a camel. In such a case, his clarification is insignificant because when someone mentions a camel, what they mean is a camel. What he intended is superseded by what people generally mean, with the result that he’s liable to lashes. The same is true in all comparable cases.