By the early first century CE, Judaism had split into three distinct sects because of differences in PHILOSOPHY.
These three groups were identified as the Essenes, the Sadducees, and the Pharisees.
The Essenes were an ascetic and mystical group devoted to strict discipline. They lived in isolation from the world.
The Sadducees sect was made up of the priests and the aristocrats of Jewish society. They were religiously conservative but socially liberal. They believed in a strict, narrow and unchanging interpretation of the written Torah, and they did not believe in the oral Torah.
The Pharisees believed that God gave the Jews both a written Torah and an oral Torah, both of which were equally binding and both of which were open to interpretation by the rabbis, people with sufficient education to make such decisions. The Pharisees were devoted to study of the Torah and education for all.