Pharisees were at various times a political party, a social movement, and a school of thought in the Holy Land during the Second Temple period, beginning under the Hasmonean dynasty (140–37 BCE) in the wake of the Maccabean Revolt. After the destruction of the Second Temple in 70 CE, Pharisaic beliefs became the liturgical and ritualistic basis for Rabbinic Judaism(commonly known as simply Judaism).

Conflicts between Pharisees and Sadducees took place in the context of much broader and longstanding social and religious conflicts among Jews, dating back to the Babylonian captivity and exacerbated by the Roman conquest. One conflict was class, between the wealthy and the poor, as Sadducees included mainly the priestly and aristocratic families.^[1] Another conflict was cultural, between those who favored Hellenization and those who resisted it. A third was juridico-religious, between those who emphasized the importance of the Second Temple with its cultic rites and services, and those who emphasized the importance of other Mosaic Laws. A fourth point of conflict, specifically religious, involved different interpretations of the Torah and how to apply it to current Jewish life, with Sadducees recognizing only the Written Torah and rejecting doctrines such as the Oral Torah and the Resurrection of the Dead.

Josephus (37 – c. 100 CE), himself a Pharisee, estimated the total Pharisee population prior to the fall of the Second Temple to be around 6,000 ("exakischilioi").^[2] Josephus claimed that Pharisees received the backing and goodwill of the common people, apparently in contrast to the more elite Sadducees. Pharisees claimed Mosaic authority for their interpretation^[3] of Jewish Laws, while Sadducees represented the authority of the priestly privileges and prerogatives established since the days of Solomon, when Zadok, their ancestor, officiated as High Priest. Josephus' statement 'common people' strongly indicates that most Jews were 'just Jewish people' by separating them, and making them independent of the main liturgical groups. The New Testament also makes common reference to the common people indicating that the Jewish identity was independent and stronger than these groups. In his Epistle to the Philippians, Paul of Tarsus claims that changing liturgical sects in the Diaspora had occurred while still identifying oneself as 'Jewish' or 'Hebrew', 'circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; in regard to the Law, I am a Pharisee', but the position of Paul of Tarsus and Judaism is still disputed.

Outside of Jewish history and writings, Pharisees have been made notable by references in the New Testament to conflicts between themselves and John the Baptist^[4] and with Jesus. There are also several references in the New Testament to Paul of Tarsus being a Pharisee.^[5] However, the relationship between Early Christianity and Pharisees was not always hostile, e.g. Gamalielis often cited as a Pharisaic leader who was sympathetic to Christians. Christian traditions have been a cause of widespread awareness of the Pharisees.