Greek synagōgē — "a gathering together, assembly" — used in the Septuagint to translate Hebrew kenesset or edah. As an institution, the synagogue emerged during or after the Babylonian exile (6th century BC) when the exiled Jews, cut off from the temple in Jerusalem, needed a place to gather for prayer, Scripture reading, and instruction. By the first century, synagogues existed in every Jewish community of any size across the Roman Empire — in Jerusalem alone ancient sources claim hundreds — and in every town of the diaspora from Babylon to Rome to Alexandria. A minyan of ten adult Jewish males constituted a synagogue.
The synagogue is critical for understanding NT Christianity's institutional inheritance. Five observations. (1) Jesus' primary teaching venue. "He went into the synagogue on the Sabbath day" is a refrain in the Gospels. Jesus was a synagogue preacher; He read the Isaiah scroll in the Nazareth synagogue (Luke 4:16-30), taught in Capernaum's synagogue (Mark 1:21), and healed on the Sabbath in multiple synagogues. (2) Paul's missionary base. Paul's standard strategy was to enter a city and go to the synagogue first — where he found Jews who knew the Scriptures and God-fearers already sympathetic to monotheism. Most Acts chapters 13-28 synagogue scenes show this pattern. (3) Church structure inherits much from synagogue structure. Elders, prayer, reading of Scripture, exposition, and psalm-singing all carried over. The NT word ekklēsia (church) is functionally the new-covenant equivalent of synagogue. (4) Separation was gradual. For about 60 years after Christ, Jewish-Christian believers often worshipped in synagogues until increasing conflict led to the Birkat HaMinim (c. AD 90) — a synagogue prayer against heretics (Christians) that effectively excluded believing Jews. (5) Enduring significance. The institution continues in Jewish life today. Christians reading the NT synagogue scenes are not reading about a dead institution; they are reading about the ancestor of every Reformed worship service that features Scripture reading, prayer, and teaching.