If the question of the belief in one God is discussed by many people as the general religious principle which is characterized for monotheist practices, the issue of Israel’s unique responsibility to God is often perceived as rather provocative. Theologians pay much attention to discussing this controversial question with references to the Jewish history and development of the religious practices and ethics. Epstein provides his vision of the issues basing on the discussion of these questions as the cornerstones of Judaism which were developed with references to the Jewish history and religious tradition. Thus, the main principles of Judaism are the belief in one God as a result of Abram’s converting his people in monotheism and Israel’s unique responsibility to God because Israel’s nation is chosen by God. Abram is an important figure in the history of the Jewish spiritual development. Thus, Abram is discussed as the founder of a new nation and a person who led his people to monotheism. According to Epstein, “Abram broke with idolatry and turned to the service of the one and only God whom he recognized as the Creator of heaven and earth” (Epstein 12). This fact can be analyzed as the starting point for developing the main principle of Judaism which is the belief in one God. Abram’s nation is discussed as having the unique knowledge of God because the Jewish people are chosen by God. From this point, these people are characterized by “a national mark of consecration to the service of God” (Epstein 14). Therefore, the religious monotheism develops along with the ethical monotheism. According to the Jewish Law, the main principles in relation to which people should live are Justice and Righteousness where Righteousness is closely associated with the definite duties. The orientation to the Jewish people’s duties and morality is referred to the Messianic thinking. All these points are connected and accentuate the Jewish people’s unique role as the providers of Justice and Righteousness in the world basing on the life of holiness. Thus, Israel as ‘the champion of God’ has the definite priestly mission in the world depending on the Jewish people’s role as the nation which is chosen by God. That is why, much attention is paid to following the concepts of personal and social morality in relation to the Jewish Law as it is represented in the Torah (Epstein). Being the nation which should spread the ideas of holiness in the world, the Jewish people concentrate on the discussion of virtues and their significance as these notions are presented in the Torah. Following the idea of personal morality and responding to the social laws, the Jewish people should orient to their virtues and inner holiness, but not to their instincts. In this case, the principles of Justice and Righteousness are also realized completely. To conclude, it is important to note that the belief in one God in Judaism is based on the ideas of monotheism developed by Abram as the reaction to his father’s polytheist vision and to his unique role of a founder of the new nation. Moreover, Israel’s responsibility to God is explained by the vision that the Jewish nation is chosen by God, and its role is to spread the ideas of Justice and Righteousness in the world, basing on the life of holiness wh