Maimonides teaches a fundamental purpose to our observance of the Sabbath: to display a deviation from other nations, as we rest, while they work. This is to induce a question from other peoples, so that we might explain our strange behavior: we are mimicking the Creator Who rested on the seventh day. Through our rest, and response, we successfully imbue others with the knowledge of Godís existence, and His exclusive role as Creator.
Other laws insulate the Jew from intermarriage, such as drinking with idolaters, for fear, lest we marry their daughters through close ties forged in the act of drinking. Not that all drinking is prohibited, or all parties forbidden, for some parties are merely to sustain friendships with coworkers, and in fact, do not contain any alien, religious ceremonies, although labeled as such. This article is not meant as a halachik ruling but as a suggestion.
We have another opportunity to remain true to Jewish philosophy by abstaining from Christmas parties. Our country guarantees freedom of religion, for which, we must be grateful to God, and the United States. Never before were Jews offered the opportunity to flourish in our Judaism with no oppression, and even with respect. By abstaining from Christmas parties, we must not fear the ridicule of others, for we know God gave Judaism as the only religion to mankind. Such parties quite often enforce the false religion of Christianity into Jewish consciousness. Unless our job is at stake, we are wise to refrain from attendance, even if the party is not of any religious nature, but merely an office gathering. For idolatry is the antithesis of Judaism, and God.
†We do not proselytize, but we must remain focused on truth, and refrain from any recognition of idolatry. We do not enter Churches for this reason. If asked, we can very politely explain our reason for our absence at such parties: the Jewís role is to adhere to monotheism, and educate the masses when inquired. By recognizing other religions as we join in their parties celebrating Jesus, we fail in our role designated by God, and harm ourselves, as we compromise eternal Torah virtues, for the sake of fleeting vanities. By not attending these parties, we remain true to Godís law, and afford others an opportunity to inquire and learn the difference between idolatrous rites and Jewish law; between fantasy and absolute truth; between false religions, and the only true religion given by God.