Fresh out of the yeshiva, I spent my first year in the rabbinate in a lovely American small town. My congregants were warm, fine people, but I was the only fully observant Jew. At the time, a veteran rabbi asked me if the experience had strengthened my Jewishness or weakened it. Without hesitation, I replied that it had been strengthened. The very need to explain and to respond to challenges had forced me to become a more alert and more knowledgeable Jew. I thought of this recently when I saw a Jerusalem real estate advertisement that declared, "A Home for Every Hashkafa/Ideology." It listed various homes in different neighborhoods ranging from Hassidic to haredi to modern Orthodox to secular and beyond. Whatever a person's ideological/theological requirements, this company had a neighborhood to meet those needs. Unspoken in the ad was this idea: Why live with people who are not exactly like you, who do not exactly replicate your personal way of life? You can choose to live with people who are carbon copies of you, who dress like you, pray (or don't pray) like you, think like you, behave like you. Why suffer even a twinge of discomfort when you can find a niche that fits you perfectly, that never challenges you and that never questions you. The advert proclaimed that the prices were within the reach of everyone. What they omitted was the long term cost. For if a person lives in a neighborhood where everyone is identical, that means that he never has to engage anyone in a serious discussion about his way of living. And when one never has to think about what they are doing or why, the danger is that a person will soon be acting thoughtlessly and by habit - what the prophet derisively calls mitzvat anashim melumada - serving God by rote. And if there is nothing to discuss, the danger is one of atrophy and boredom and complacency and, ultimately, intellectual decay. That is a high price indeed. ONE CAN understand the natural desire of people to live in a neighborhood that is compatible with their way of life and beliefs. But supposing someone ventured to live in a neighborhood with people who did not share the same hashkafa, what major catastrophe might ensue? If my next door neighbor wore a black hat while I wore a colorful knitted yarmulke, what might happen? Would my children be ruined religiously by the knowledge that there are others who are different? And if my neighbor observed the Shabbat while I did not, would that leave a black mark on my soul - or on his? Are we so insecure in our theology, so fearful that it will fall apart if challenged, that it needs to be validated by a monolithic neighborhood every time we step outside? Obviously, we will not soon witness a mass movement of Haredim into secular neighborhoods, or of non-observant Jews into observant areas. This is a pity, because among the many problems we face in Israel is that of the rigid barriers that exist between the various groups. No one is talking to anyone but like-minded people. Does a kippa seruga talk to a shtreimel? Does a black hat talk to one who wears no head covering - or to a kippa seruga? Does the lady with the sheitel and the woman with the uncovered hair ever communicate with one another? Do Belzer Hassidim talk with Breslov Hassidim? Do Ashkenazim talk with Sephardim? The insularity - even within groups who have identical beliefs - is palpable. The barriers are even more impermeable than the security barrier being constructed between us and the Arabs. Men are religiously pigeonholed by the length of their jackets, the width of their hat brims, and the color of their shirts, and women by whether they wear a hat, a wig, a snood, or no hair covering at all. And there is little acknowledgment of the existence of anyone who is slightly different. I WONDER if there is out there an occasional person with the inner fortitude to move into a neighborhood that does not match his precise ideology. Is there a Hassidic Jew who would move into a secular area - and would a secular Jew greet them without fear, or flee the neighborhood? Or is there a secular Jew who would choose to live among haredim - and would haredim treat them decently, or move elsewhere? What might happen in such a mixed neighborhood? Granted, the secular Jew might do things on Shabbat that would disturb the tranquility of the observant Jew. He might, for example, roar off in his car during the recitation of Friday night kiddush. Then again, he might not. He might decide that on Shabbat, though he does not practice it, he would out of deference to his neighbor avoid doing anything that might be offensive religiously. And they might even learn from one another. The secular Jew might learn that the observant Jew is not a monster, that he is not engaged in religious coercion, and that although he observes Shabbat and attends synagogue daily, he is not a wild-eyed fanatic, but a very decent human being. And the observant Jew might discover that his secular neighbor, though he wears no head covering, is always ready to be a good neighbor, to help him in a thousand ways, and is a real mensch. No one's core beliefs would be affected. And the ultimate oneness of the Jewish people might even be strengthened. Well and good, you might say. But what about my children? Will they not be negatively affected by contact with those who are so different from what they are taught at home? Not necessarily. They might even be strengthened in their Jewishness, like the young rabbi in our first paragraph. Jewish children who are secure in their own beliefs and practices can only be invigorated and fortified by meeting other Jewish children of different beliefs. If they ask their parents why this and why that, the theology of the parents could only be strengthened by the need to explain and to help their children - and themselves - understand who they are. In this way, children and adults would also learn how to live in the real world where not everyone is alike. They can be helped to grow by learning that there are differences, and to learn to tolerate and understand those differences. Ultimately, when we all get to the World-To-Come, we will not be asked about the kinds of jackets we wore, or the colors of our shirts, or the types of head coverings. We will be asked if we were honest, decent people, if we were loyal to our Jewish heritage, if we tried to build a future generation of faithful Jews, if we did not despair about the condition of the Jewish people but kept alive our faith in the ultimate redemption. We all know why the Messiah has not yet appeared. The chances are that he is actually here, waiting at the gates of Jerusalem. But he cannot enter, because he does not know what kind of garb to wear. If he wears all black, the kippa seruga crowd and the secularists will be afraid of him. If he wears a kippa seruga , the "black" crowd will shun him. If he wears a black hat but not a shtreimel, he will be ostracized by certain Hassidim. If he wears black with a shtreimel, it might not be the right kind of shtreimel. The possibilities and choices are infinite. So there he stands at the gates ready to enter, but troubled by serious sartorial issues. In his suitcase is a white shirt, black trousers, a colorful sweater, a sport jacket, a long black kappotte, a black hat, a multi-colored kippa seruga, and several styles of shtreimel. But he prefers to travel light, and he cannot enter with this burdensome wardrobe. And so he waits - for us to decide what he should be wearing, and for us to decide what worldview we will be following. But once he makes it through the gates, he carries in his hands the text of his own real estate ad: "Homes available in the new Messiah Ben David community - regardless of hashkafa. Come as you are. All are welcome." The author served as a rabbi for 40 years in Atlanta and is former editor of Tradition magazine. He is presently on the editorial staff of The Encyclopedia of Mitzvot.