Question:
When was the first synagogue (Beis Haknesses) built? Did shuls exist during the times of Moshe Rabbeinu and the First Beis Hamikdash? Obviously, I understand that the Mishkan and Temple was the first official “Shul” designated for serving Hashem. I am more referring to shuls as we know of them today, for Davening with a Minyan, Shacharis, Mincha and Maariv.
Answer:
The exact date of the first synagogue is unclear. However, it appears clear that shuls, as we know them today, did not exist during the times of Moshe Rabbeinu, nor during most of the era of the First Beis Hamikdash when formal communal prayer did not yet exist. Rather, they seem to have developed towards the end of the First Temple period and especially during the Babylonian exile.
The earliest source often cited is the verse in Yirmiyahu 39:8: “And the Chaldeans burned the king’s house and the houses of the people with fire.” Rashi explains that “the houses of the people” refers to synagogues (Batei Kenesiyos), implying that synagogues already existed near the end of the First Temple era.
Likewise, the prophet Yechezkel referred to synagogues as a “Mikdash Me’at”—a miniature sanctuary—and Chazal explain that when the Jewish people were exiled, Hashem’s presence would rest in the synagogues and study halls in place of the Beis Hamikdash.
Nevertheless, the institution of the synagogue in its familiar form appears to have developed mainly after the destruction of the First Beis Hamikdash. During the Babylonian exile, the Jewish people lacked a Temple in which to gather and serve Hashem. As a result, communal places of worship and Torah study became necessary. The synagogue likely originated as a permanent institution during the period of the exile. After the return from Babylon, Ezra and the Anshei Knesses Hagedolah established the fixed structure of prayer, and synagogues became the central locations for communal worship and Torah study.
During the Second Temple period, synagogues already existed both in Eretz Yisrael and throughout the Jewish diaspora. Archaeological discoveries have uncovered a synagogue in Gamla in the Golan Heights that remained in use until the Great Revolt. Likewise, the Yerushalmi relates that before the destruction of the Second Beis Hamikdash there were 480 synagogues in Jerusalem. Additional evidence for the existence of synagogues in Jerusalem during the Second Temple era comes from the famous Theodotos inscription discovered in the City of David. At the same time, historians note that there is no conclusive evidence that these synagogues functioned primarily as houses of prayer in the manner familiar today, and they may have served chiefly as centers for Torah study, communal gatherings, and public affairs.
Interestingly, while synagogues certainly existed during the Second Temple period, there is little evidence that they were primarily used for formal prayer at that time. Only after the destruction of the Second Beis Hamikdash did the synagogue assume its role as the central place for communal prayer, serving as a substitute for the Temple service.
By the time of the Talmud the synagogue had already become a central institution of Jewish life. The Gemara in Tractate Brachos and Megillah discusses countless laws relating to synagogues, including their construction, sanctity, maintenance, proper conduct within them, public Torah reading, communal prayer, and the various activities that took place in them. Thus, while the precise origin and date of the first synagogue remain unclear, it is certain that throughout the Talmudic era the concept of the Beis Haknesses was already firmly established and an integral part of every Jewish community.
Conclusion:
While the exact location of the first synagogue is unknown, it appears that synagogues began to emerge towards the end of the First Temple period and became established during the Babylonian exile. The synagogue then expanded during the Second Temple era and became the central institution of Jewish communal prayer after the destruction of the Second Beis Hamikdash.
Sources:
Yirmiyahu 39:8 with Rashi; Yechezkel 11:16; Yerushalmi Miseches Brachos 5:1; Yerushalmi Megillah 3:1; Bavli Brachos 4b; 6a; 8a-b; 21b; 27b; 47a; Megillah 5a; 18b; 21b; 26a; Rambam Hilchos Tefillah 1:4