An interesting question, to be sure, but a sad one as far as I am concerned.
First of all, I commend you and your congregation for doing a wonderful and charitable deed by helping these unfortunate people. That is certainly very commendable.
But I don't think that your act of charity should be at the expense of violating the sanctity of your temple. A Synagogue, or Temple, represents to us a place of great Holiness, in which we remember the great Temples in Jerusalem of old, and look forward to their rebuilding speedily in our days. That temple was a “Place of worship for for all Peoples” (Isaiah 56:7), meaning not, G-d forbid, that crosses and Christmas trees and Buddhas etc were brought in, but that all humans will be invited to worship the one and only God, the God that we Jews believe in. We welcome all others, we wish to help them, and bring them close to God, but not by helping them to celebrate the holidays of other religions.
Furthermore, having a Christmas tree in the synagogue cannot but be confusing, at best, to the congregants, especially to the children. (I would assume that many of those children already wonder why they do not have a Christmas tree at home; try explaining our different attitude when they see a Christmas tree in the temple!) Whether or not a tree is really religious or pagan is beside the point – it is clearly a symbol of Christmas, and does not belong in the Temple. In addition, you make an excellent point that paganism was a far worse form of idolatry than Christianity, as it is not at all clear that Christianity is idolatry for non-Jews (it is for Jews – I refer you to an exhaustive treatment here by a conservative scholar), while it is absolutely clear that paganism is.
It seems to me that the easy alternative would be to pick a different week, as you suggest. The more challenging, but ultimately very worthwhile alternative would be, in my view, to clearly welcome these people as a Jewish institution, with very Jewish themes in place (Chanukah menorahs if it is Chanukah, etc) . Make it clear to them that we are not trying to proselytize, but that at the same time we are proud of our heritage and our tradition, and welcome them to experience it at this “Holiday” time.
If they are offended by that, so be it. My guess would be that we would win more friends and respect for clearly standing for who we are, and from that position, sharing our kindness with others.
Answered by: Rabbi Yehuda Leonard Oppenheimer