Shammai and Hillel
In the period before 70 A.D. most of the training was centered in the ‘schools' of Shammai and Hillel. After 70 A.D. that of Hillel had a dominant position.
Shammai is usually thought to have been more conservative and Hillel more liberal. Hillel came from Babylon to Jerusalem as an adult, while Shammai spent his whole life in Judea. Otherwise very little is known about them and their work. Many of their apparent views come from accounts by their followers from the time after 70 A.D. and it is far from certain that these are always authentic. In Pirqe Aboth (m.Aboth I,II) Shammai and Hillel are the fifth and most famous pair of those who handed down oral teaching from the time of Moses to their own day.
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