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In page Pharisees:

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Pharisaic wisdom was compiled in one book of the Mishna, Pirkei Avot. The Pharisaic attitude is perhaps[citation needed] best exemplified by a story about the sages Hillel the Elder and Shammai, who both lived in the latter half of the 1st century BCE. A Gentile once challenged Shammai to teach him the wisdom of the Torah while he stood on one foot. Shammai drove him away. The same gentile approached Hillel and asked of him the same thing. Hillel chastised him gently by saying, "That which is hateful to you do not do to another; that is the entire Torah, and the rest is its interpretation. Go study."[1]