The survival of our Jewish people, and the impact that this matter has on every Jewish individual, is not something which has yet to be investigated and experimented with. The Jewish people is one of the oldest in the world, and in its long history as a nation it has gone through various conditions and circumstances, mostly very unfavorable. If one wishes to know the secret of Jewish survival under circumstances which have obliterated larger and stronger nations, one has but to apply the same scientific method as in other cases. In other words, it is necessary to find the common factor, or factors, in all the various periods of Jewish history, which would then have to be taken as the basis of Jewish survival. Should two or three different factors be found, there would be the question of whether all of them were indispensable to survival, or perhaps only one or two would also have been sufficient. But if only one common factor is found, then there can be no doubt that this is the only basis of the survival…
Now, going back to the long history of our Jewish people over a period of some thirty-five hundred years, it will be seen that there has been only one factor which has preserved Jewish identity and survival throughout the various periods of our history. This factor was not language, nor country, nor anything else which is often associated with nationhood and nationalism; for in all these things there have been radical changes from one period to another, as anybody familiar with Jewish history knows. The single factor, and I emphasize, the one and only factor, which has preserved our Jewish people throughout the ages, under all kinds of circumstances, has been the fulfillment of the mitzvos in day-to-day life, such as the observance of Shabbos, the putting on of tefillin, and the Torah education of our children. These and all other mitzvos are already embodied in the Torah and have been observed by Jews since the Torah was given at Mount Sinai, and they have been observed in the same way throughout the ages, without change.
Rebbe’s letter. Chabad.org/therebbe/letters - The key to Jewish survival
Yom Habohir Gimmel Tammuz. Most mivtzos are mitzvos maasios – Action mitzvos. The first approach is to get a Jew to do a mitzvah – mitzvah goreres mitzvah. Secondary, is hashkafa and philosophy.