Members of an e-mail list were debating whether it is better to wish someone an easy fast or a meaningful fast. Dr. Yitzchok Levine replied:
R. Yisrael Salanter is quoted as saying something like, "The other person's gashmius is your ruchnius." He did his best to live his life by this principal.(Reprinted with permission from the author and the moderators of the list. Includes very light editing.)
I have always taken this to mean that one should worry, for example, if the other person has food to eat as opposed to whether his tefillin are kosher. The statement, "Have an easy fast." concerns the other person's gashmius. I do not feel that it is my place to worry about his ruchnius by saying "Have a meaningful fast."
Indeed, when people have said to me, "Have a meaningful fast" it has always sounded strange to me. Meaningful according to whose standards and in what sense?
So, to all readers, I say, "I hope that you have an easy fast!"