In the face of dramatic changes in the structure of the Jewish community in the modern era under the influence of the Enlightenment, widespread abandonment of Torah and mitzvot, and nationalism, Jewish thinkers were required to respond to new questions and formulate original insights concerning the purpose of the Jewish people and the place of Torah in the new world. Modern Jewish thought contends with various changes that have taken place with regard to Jewish life. One change stems from the growing influence of external, non-Jewish elements, which necessitates a redefinition of Jewish identity and the delineation of the boundaries between sacred and secular, tradition and progress, and the Jewish people and the nations of the world. Another change relates to the physical circumstances of the Jewish people: Migration to the Land of Israel from the Diaspora and the need to assume responsibility for the renewal of Jewish settlement there, migration to the New World, and active participation in the development of science and culture. All of this necessitates a reconceptualization of the uniqueness of the Jew and his role in a changing world.

Rabbi Yisrael Lipschitz (1782–1860) was the rabbi of Danzig. His main work was Tiferet Yisrael, a commentary on the Mishna that includes the translation of difficult passages into German. The commentary is divided into two parts: Yakhin, written in accordance with the text’s straightforward meaning; and Boaz, novellae. It includes an introduction to each order of the Mishna in which he explains complex halakhot, e.g., the sanctification of the month, the setting of the Jewish calendar, the structure of the Temple, and leprous marks. He appended an essay, Derush Or HaĤayyim, to his commentary on Nezikin. In it, he discusses paleontological and geological discoveries made in his day, such as fossils, and explains them in the context of faith in Creation.

From Rabbi Yisrael Lipschitz:

In-depth study means that one should not move on from something he has learned until he has asked himself seven questions and answered them: who, what, to whom, when, where, how, and why. When one knows the answers to all seven of these questions, everything difficult and complex will become clear.

Rabbi Samson Raphael Hirsch (1818–1888) was born in Hamburg, Germany, and served as the rabbi of various cities in Bohemia and Moravia, and then in Frankfurt, Germany. His books Nineteen Letters and Ĥorev are concerned with the revelation at Sinai, and they explain the Torah’s commandments to the younger generation. He translated the Torah into German and also wrote a broad commentary on it, which emphasizes the symbolism of each mitzva. In his commentary, he uses creative etymological tools similar to those employed by the Sages.

He established schools in accordance with the motto: Torah im derekh eretz, Torah with the “way of the land.” His outlook encourages the combination of Torah study and general studies, and views the Jew’s integration into society in a positive light. Rabbi Hirsch opposed religious reformers, rejected the changes that they made due to the changing times, and emphasized the importance of religious action, and not merely having faith. At the same time, he believed that Jews are obligated to acquire an education and earn a livelihood, and to relate to the universal human experience. In this respect, Rabbi Hirsch is responsible for shaping the image of the Orthodox German Jew, who is as careful about minor mitzvot as he is about major ones, works for a living, and is sensitive to societal etiquette and customs, as well as to those with whom he interacts.

From Rabbi Samson Raphael Hirsch:

In nature, phenomena are recognized as facts even if you do not yet comprehend their causes or interrelationships; their existence does not depend on the results of your investigations. The same is true with regard to the Torah’s commandments; they are law for you…. Your fulfillment of a mitzva must not depend on your investigation of it.

Rabbi Avraham Yitzĥak HaKohen Kook (1865–1935) was born in Griva, Latvia, and served as a rabbi in Bauska, Latvia, and then in Jaffa and Jerusalem. Subsequently, he was appointed as chief rabbi of Palestine.

He wrote works of halakha and aggada. His halakhic works deal extensively with mitzvot that are dependent on the Land of Israel. The halakhic basis that he provided for the selling of land to gentiles during the Sabbatical Year is well known, as is his work Halakha Berura, which summarizes the halakhot in relation to their talmudic sources. In the domain of aggada, he wrote Ein Aya, a commentary on the aggadot in tractates Berakhot and Shabbat.

Most of his philosophy can be found in his work Orot HaKodesh, a collection of passages written in a poetic style, which describe the development and progress of humankind and of the world. He accorded theological-mystical significance to Jewish nationalism, although he criticized its pioneers and leaders for abandoning the observance of the mitzvot. He was strongly criticized for his positive attitude toward Zionism and boycotted by members of the ultra-Orthodox communities that had existed in the Land of Israel in the centuries prior to the waves of Zionist immigration. Nevertheless, he established the Central Universal Yeshiva and supported the Zionist enterprise in accordance with his worldview.

From Rabbi Avraham Yitzĥak HaKohen Kook:

The pure, righteous ones do not lament over evil; rather, they increase righteousness. They do not lament over heresy; rather, they increase faith. They do not lament over ignorance; rather, they increase wisdom.

Rabbi Ben-Tziyyon Meir Ĥai Uziel (1880–1953) was born in Jerusalem and was a rabbi in Tel Aviv, Jaffa, and Thessaloniki, after which he was appointed as the Sephardic chief rabbi of the Land of Israel.

His main works are Mishpetei Uziel, which consists of halakhic questions on many topics, and Hegyonei Uziel, on matters of faith and Musar. He was appointed as the Ĥakham Bashi at age thirty-one, representing the Jews before the Ottoman authorities, and later before the British commissions for partition. He was popular and tried to bring people together in peace.

He dealt with many contemporary issues: He worked to abolish the conscription of thousands of Jews to the Turkish army, and prevented harm from coming to the Jewish community when the Nili underground organization was discovered. He also worked to strengthen supervision of kosher food and the status of the rabbinate in the Land of Israel, and he established institutions for the study of Torah. Toward the end of his life he was appointed as a member of the Jewish National Council and a representative of the Jewish Agency.

From Rabbi Ben-Tziyyon Meir Ĥai Uziel:

Remove all causes of division and dispute from our camp and from our country, and replace them with all the causes of peace and of unity between us, and our camp will become pure and sanctified, fortified and unified…. God, who makes peace in His heights, will make peace for us and bless us.

Rabbi Yeĥiel Yaakov Weinberg (1884–1966) was born in Russia, studied at the Mir yeshiva, and became acquainted with Rabbi Natan Tzvi Finkel, the Alter of Slabodka. Rabbi Weinberg, who was the head of the rabbinical seminary in Berlin, was imprisoned in work camps during the Holocaust. He died in Montreux, Switzerland.

He was a preeminent halakhic authority, and answered questions on a wide range of topics, including: stunning an animal with an electric shock before slaughtering it, disinterment of the remains of the dead, mixed-gender youth movements, bat mitzva celebrations, and the status of the children of a marriage between a Jew and a non-Jew. His book of responsa is called Seridei Esh, “the remnants of the fire,” because most of his writings were destroyed during the Holocaust. Some of his other writings are collected in the book Lifrakim.

In his youth, he spent time among the followers of the Musar movement in Lithuania. Subsequently, he studied at university in Berlin, and was then appointed as the head of the rabbinical seminary. In addition to teaching and training rabbis, he was involved in talmudic research. Rabbi Weinberg managed to merge the approaches of Musar, academics, and classical rabbinical thought. Furthermore, his thinking was sharpened by a unique level of sensitivity due to the terrible suffering that he experienced during the Holocaust.

From Rabbi Yeĥiel Yaakov Weinberg:

We see in Judaism a lofty vision, filled with glory: The development of creativity within the framework of observance. Creativity is constantly being renewed, while observance remains unchanged. The contents are fluid, while the form is fixed…. Although the reasons for the mitzvot have changed, and will change again in every generation and in each spiritual era, their practical fulfillment has not changed, nor will they ever change.

Rabbi Yosef Dov Soloveitchik (1903–1993) was born in Pruzhany, Belarus. His father was his primary teacher of Torah, and he studied philosophy at the University of Berlin. He served as a rabbi and professor of philosophy in Boston and New York.

He wrote a number of influential philosophical treatises, including Halakhic Man, on the philosophy of halakha, and The Lonely Man of Faith, on the existential condition of the believer. Additionally, his Talmud lectures, given in the analytical style of his grandfather, Rabbi Ĥayyim Soloveitchik, have been published, as have other works on various topics in Jewish thought.

He was one of the leaders of American Jewry, and shaped the image of the Modern Orthodox American Jew. His works are considered to be among the most brilliant and challenging in the field of Jewish thought. He endeavors to conceal his passionate experience of Judaism beneath his rational and complex style.

From Rabbi Yosef Dov Soloveitchik:

Prayer is a vital need of a religious person. He cannot stop the thoughts and feelings that are in the depths of his soul, the doubts and hardships, the longings and yearnings, the despair and bitterness. In short, the great abundance that is concealed within his religious consciousness…. Prayer is essential. It is impossible for living, invigorated religious feeling to endure without it.