So, about Zacchaeus.... Now I'm not sure how interested you are in this subject. I assume most of you don't click over here for sermons or history lessons. But humor me, because this Biblical figure is quite interesting to me, for good reasons, which I'll share at a later time. For now...
Following our look into the Biblical figure, Zacchaeus, we ask the question: How did Jewish custom or law perceive those Jewish men who opted to become Roman officials by way of the publican, or tax collector?
The Talmud, which began as an oral tradition or law explaining what the Torah (Genesis - Deuteronomy) means and how to interpret the five books and apply the Laws therein, was compiled and written down around the 2nd century C.E., after the fall of Jerusalem and her temple in 70 C.E. Orthodox Jews believe God taught the oral law (Talmud) to Moses, and he taught it to others, down to the present day. It is from the Talmud that we draw societal conclusions and laws governing Jewish tax collectors.
We know that during the time of Christ on earth, the Pharisees were the Jewish sect that strictly followed this oral tradition. In fact, it was a Pharisee that later compiled the written Talmud in 2nd century C.E. What we don't know is how much weight these laws had with the other sects of Judaism at the time of Christ.
I have not gone to the original sources here but rather take mostly from the writings of Alfred Edersheim, a Messianic Jewish scholar of the late 1800's in The Life and Times of Jesus the Messiah. Brief internet sources are cited.
1. The lawfulness of paying Roman taxes was questioned by Rabbinical teaching. Why? For one, Roman rule over the Jewish nation was against the expectation, hope, and redemption of Israel. The Jewish publican was seen as the embodiment of antinationalism, a man gone to work for the other side, so to speak. And second, religious conviction, especially of the most devout Jews, demanded no homage to any lord but the one true God.
2. There were two types of tax collectors. Those who collected the regular dues of ground, income, and poll tax. And the custom house official, of greater Roman importance, and the object of chief hatred. It was the custom house official that could inflict greater hardship on the people, taxing them on anything imaginable. Imports, exports, all bought and sold, road money, harbor dues, axles, wheels, animals, bridges, etc, etc. Even the research of modern scholars has not been able to identify all the names of exacted dues. Tax collectors often stopped travelers on their journeys, forcing them to unload all goods, animals, and searching through private letters and such. Quite an annoyance to any traveler in route to a necessary destination.
3. Both classes of publicans fell under a Rabbinic ban: Tax collectors were disqualified from being judges or witnesses in law suits, because they "exacted more than was due." It was also believed and stated that repentance was especially difficult for tax-gatherers and custom house officials. Jews were forbidden the changing of money from the chest of the custom house officials who did not keep to the tax appointed by the government. Those that volunteered their service to Rome did so in hopes of making profits on their own account. Or at least that is how they were viewed. The Talmud charges the custom house officials with gross partiality, showing favor to those they wished, and exacting from those who they did not favor. They were considered a criminal race. If a Jewish tax collector belonged to a sacred association, they were at once expelled, though restoration was possible through repentance. They were said to be oppressors, and against them every type of deception was allowed so as to avoid their oppressions.
4. Records of the brutality of the tax collector: Recorded by Philo (30 B.C.E - 45 C.E.), Hellenized Jewish philosopher from Alexandria, Egypt: "They [Romans] deliberately choose as tax collectors men who are absolutely ruthless and savage, and give them the means of satisfying their greed. These people who are mischief-makers by nature, gain added immunity because of their "superior orders," obsequious in everything where their masters are concerned, leave undone no cruelty of any kind and recognize no equity or gentleness . . . as they collect the taxes they spread confusion and chaos everywhere. They exact money not only from people's property but also from their bodies by means of personal injuries, assault and completely unheard of forms of torture." From De Specialibus Legibus (http://www.taxhistory.org/thp/readings.nsf/cf7c9c870b600b9585256df80075b9dd/a5321448c7e17ff185256f0a0059a4ba?OpenDocument)
5. Records of favorable Jewish publicans: There are cases of recorded religious custom house officials showing favor to Rabbis, or giving them notice to go into hiding. There is an instance related of a tax gatherer becoming a Rabbi, though the more rigid of his Jewish brothers refused association with him.