What is the largest Jewish congregation in New York City?

The largest Jewish congregation in New York City is Emanu-El, which is located on the Upper East Side. Founded in 1845, it has a significant membership, which reflects its long-standing history and extensive community activities. The congregation is known for its prominent and beautiful sanctuary, which is designed in the Byzantine style, and it plays a vital role in the Jewish community by providing a wide range of religious, educational, and social services.

In contrast, the other options either do not match the scale of Emanu-El's congregation or serve different functions within the Jewish community. For instance, Or Zarua is a much smaller congregation that caters to a specific community, while Temple Israel also serves a specific neighborhood within its own capacity. Hebrew Union College, while an important institution for Jewish education and training of clergy, is not a congregation in the traditional sense but rather a seminary, thus making Emanu-El the standout choice based on congregation size and influence.