Well, it's a fair question. There are lots of movements out there in the world that either never should have been started or addressed a specific concern at one time which is no longer relevant. Any group of people with an ideology or agenda must be prepared to answer the question: What justifies your existence? Modern Orthodoxy is no different.
In order to suggest an answer to this question, one must ask what Modern Orthodoxy is. Unfortunately, there is no easy answer to this question. Various writers on the subject note concepts like ideological Modern Orthodoxy and behavioural Modern Orthodoxy. Others label it as Judaism-lite, a refuge for those Jews who wish to call themselves faithful to the tradition of our fathers without committing to a serious lifestyle change that would set them apart from the secular world they live in. In other words, it's hard to say what Modern Orthodoxy is, only what it isn't.
One place to start, then, is to look at other Orthodox groups and see what defines them. By doing this and noting their possible weaknesses, I can possibly note some distinctions that positively define the need for Modern Orthodoxy. After all, if the local store doesn't sell milk, you can open a milk store next door to it and make some money.
The most obvious comparison is the dominant group in the Torah-observant world today: the Chareidim. The strengths of this community are obvious. They have rigidly defined ideologies, a strong sense of being distinct from the secular world around them and a good sense of group think that provides for a modicum of unity in the face of external challenges. Finally, according to their leadership, the Chareidi lifestyle is the ideal Torah lifestyle. If the point of being a faithful Jew is to live in a way of perfect consonance with Torah and its values, why is there a need to the Chareidi world?
The simple, quick answer is that not everyone can be Chareidi. This is an unavoidable fact. Whether for reasons of personal taste, views, inner values or just plain lack of interest, the challenge of leading the intense lifestyle that the Chareidim do isn't something every observant Jew can take upon themselves. If that's the case, what's the alternative?
Hold on a moment. The assumption made in the previous paragraph - IF being Chareidi isn't for everyone THEN there must be an alternative - is a pretty big one. Consider a parallel situation. Not everyone can be an NHL level hockey player. Is that a reason to create a parellel NHL for those who can't make the cut, so that they can pretend they're in the same big leagues while not meeting the actual standards? Why can it not be suggested that the Chareidi approach is the ideal and that anyone failing to live up to this ideal should accept their shortcomings and strive to come as close to it as possible?
The real answer to that is that the Chareidi assumption of idealism is erroneous. There are many ways to live a consistent Torah lifestyle, of which their approach is merely one. Therefore, one can be an observant Jew without necessarily being Chareidi. Is Modern Orthodoxy one to the approaches to allow one to fulfill one's Jewish potential, then?
(A further reason that Chareidi Judaism isn't for everyone is that community's response to the corruption within its ranks. I would venture to say that the vast majority of Chareidi Jews are honest, decent folks who are living the way they think is holiest, but a not insignificant number of evil individuals are able to tar the entire community through their behaviour. Rightly or wrongly, the Chareidi world is regarded in a negative fashion because of the many people who have had negative experiences interacting with them)
I would propose that as it is currently defined (see above), Modern Orthodoxy is not an approach to a Torah lifestyle. Let me be more specific. There is a small group within that community know in the literature as the ideological group. These are the people who believe in approach Torah and God through an appreciation of the greater world and its contents, accepting that since everything is a creation of God then learning about the universe enhances one's knowledge of the Diety. Unfortunately, these folks are in the minority.
The majority of people who define themselves as Modern Orthodox today are part of the behavioural group. As mentioned above, they are people who practice Judaism-lite. If they don't wear a black hat when they pray, it's not because they believe that wearing a certain type of skull cap or not helps one approach God in a better way. It's because they just don't want to wear the hat. If they dress in a modern fashion, it's not because this is how they choose to express their Torah values. Rather, it's because they don't want to stick out or be associated with "fanatics" of the Chareidi world.
What is needed therefore, is an approach that can take those Torah observant Jews outside the Chareidi world and provide them with a reason for being. Being modern for the sake of being modern is a useless propostiiohn, but it can also be an expression of one's Torah beliefs if the underlying reason for the push to modernity is to help one understand Torah and God better. I would therefore make a call to those who want to realize their Jewish potential without compromising their beliefs for the sake of "fitting into the mold". There is an alternative, an approach to Torah and God which can provide you with fulfilment.
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