During the period of the second temple (520 bce to ce 70) Judaism remained loyal to the past while sowing seeds for the future. It continued to maintain the temple, the priesthood, and the sacrificial cult, the legacies of the religion of pre-exilic Israel, but it also invented an institution of a completely different type, the synagogue. After the destruction of the second temple in ce 70, the synagogue gradually assumed a larger and larger role in Jewish society and consciousness. The synagogue is an enduring contribution of the second temple period to the history of Judaism, Christianity and Islam.

The origin of the synagogue is unknown, and, without a new discovery equal in magnitude to the Dead Sea scrolls, unknowable. The widely accepted theory that the synagogue originated in the sixth century bce during the Babylonian exile as a replacement for the Jerusalem temple seems plausible and attractive but is unsubstantiated and overly simplistic. Unsubstantiated, because it is not supported by a single ancient source. Overly simplistic, because it assigns to a single time and place the origin of a most complex institution. The earliest extant reference to a synagogue is an inscription from Upper Egypt from the third century bce which uses the term proseuche, ‘prayer(-house)’. The earliest known Judaean synagogue is the building erected in Jerusalem by one Theodotus in the first century bce or ce ‘for the reading of the law and the teaching of the commandments’, not, apparently, for the recitation of prayer. Ancient synagogues also served as assembly halls or community centres, much as the temple itself often did.