Are there any Jewish legal or religious traditions that run counter to celebrating Halloween, traditionally a pagan holiday, but now more or less a secular one?

Are there any Jewish legal or religious traditions that run counter to celebrating Halloween, traditionally a pagan holiday, but now more or less a secular one?

Most traditional authorities do indeed forbid Jews from participating in Halloween rituals of any kind.  The basis, from my understanding, is that Halloween has known pagan origins and that therefore, by partaking, Jews would be participating in pagan worship and would be betraying their Jewish faith.

However, as you remark in your question, Halloween has essentially lost any of its pagan intentionality.  While it is clearly true that some of the pagan symbols of holiday remain, they mostly exist to entertain.  Further, the costumes the children wear are not exclusively ghosts and witches but whatever they desire.  Therefore, I am not sure that in terms of strict halakha (Jewish law) that a firm prohibition holds.  While I admit that it could be argued either way, it is sensible to hold that children dressing up in costumes and going from door to door to get candy is not really akin to participating in pagan worship.

The question for me, therefore, is more about education.  What do our children learn from participating in what we call a “holiday” that is not a Jewish one?  If one feels that Halloween is more like Thanksgiving and one can educate their child to think of it that way, perhaps it would be perfectly fine.  If one links it to holidays of other faiths, like Christmas, I think educationally there could be a serious problem and it could result in confusing the religious identity of the child. 

This response has been running around the Web for a long time. I do not know the original source, but I also see no need to re-invent the wheel, so here it is. I agree with it completely.

Let me tell you about a wonderful Jewish holiday: once a year, our children dress up as sages, princesses, heroes and clowns. They drop by the homes of our community, visit the infirm and the aged, spreading joy and laughter. They bring gifts of food and drink and collect tzedakah (charity) for the needy.

You guessed it--it's called Purim, when it's customary to send mishloach manot--gifts of food--to one's friends and even more gifts to those in hard times.

Flip it over (October instead of March, demanding instead of giving, scaring instead of rejoicing, demons instead of sages, etc.) and you have Halloween. There you have it: a choice of one of two messages you can give to your children. I call that a choice, because one of the beautiful things about kids is that, unlike adults, they don't do too well receiving two conflicting messages at once.