Rabbi Elazar said:
Be diligent in the study the torah;
And know how to answer an epicuros,
And know before whom you toil, and that your employer is faithful, for He will pay you the reward of your labor.
Be diligent in the study the torah: diligence can either mean quick and energetic or it can mean regularity and faithful attendance.
And know how to answer an epicuros: a person should learn Torah in order to answer the questions of an epicuros. An epicuros is explained several different ways in the Talmud. He may be one who denies that there is a God, or one who denies that the Torah is of divine origin, or that , or one who despises Torah scholars. The origin of the term is the name of the Greek philosopher Epicurus, who taught that the ultimate goal of life is to pursue the pleasures of this world. He emphasized that the gods have nothing to do with human affairs. Rabbi Elazar teaches that one should know the Torah well enough to be able to engage in a debate with the epicuros. Interestingly, some commentators say that this is the reason that Jews are allowed to study Greek philosophy, for in order to know how to refute them with their own words, one must be learned in their works.
And know before whom you toil, and that your employer is faithful, for He will pay you the reward of your labor: this is connected to the previous statement, the rejection of the epicuros. A Jew must have faith in the ultimate reward and punishment for his actions. This is indeed one of Maimonides principles of Jewish faith. Unlike Greek philosophy which did not conceive of a God who was involved in the moral affairs of human beings, a God who was at most a “primal cause”, Jews believe in a God that intimately cares about how they act. The “toil” that a Jew does is before God, and not before an empty void.