Fasting for non Religious Reasons?

Question

I was recently asked to fast as a part of a multi-faith community fast as spiritual preparation for doing voter engagement work (I work for a multi-faith, multi-ethnic community organization.)

Here is what I was asked: "As a community, we will be working together to turn the voices of our communities into votes and it feels fitting to begin this journey collectively. Personally, I will be asking God to empty me of my fears and concerns and to fill me with strength and power. What will it mean to you?"

Somehow, this doesn't seem to resonate with Jewish traditions of fasting (ie mourning or strength for a time of great oppression). What does Halacha have to say about fasting for non-halachic reasons?

Answer 1

There is this (Shulchan Aruch, Orach Chaim 571:1):

One who fasts - if he is able to bear doing so, is called holy; if not - such as if he is not healthy and strong - he is called a sinner.

Mishnah Berurah there cites various authorities who apply this to voluntary fasts not in penance for specific sins; and further, that even where fasting is warranted, it is better to perform other forms of penance that won't weaken one's body, such as abstaining from unnecessary speech and studying more Torah. (R. Schneur Zalman of Liadi, in his Iggeres Hateshuvah, ch. 3, points out that tzedakah is effective for this purpose too.)

Also, Shulchan Aruch and Mishnah Berurah there note that people whose work may be impaired by their fasting - this includes full-time Torah scholars, teachers of children, and employees - must not undertake any kind of personal fasts.

All told, then, it does sound like fasting for the purpose mentioned in your question is not recommended, although of course CYLOR for practical guidance.