For the Jewish people, the Temple was the only place for complete worship.
It was the recognized center for all the Children of Israel, wherever scattered.
Indeed, the Temple was the only holy place recognized by Judaism.
The central importance of the Temple can only be fully appreciated by studying Maimonides's list of the mitzvot.
Of the 613 listed, less than half have been applicable (and some of the others only partly so) since the Destruction.
And the situation is similar in the Oral Law and in all the other areas that make up the life of the nation.
It may be said that most of the structure of Judaism was suddenly cut out from under it with the Destruction, not only in activities directly connected with the Temple and the worship there, but also a large body of mitzvot and customs indirectly bound to it.
This picture of the effect of Jewish law gives us some conception of what really occurred with the destruction of the Temple.
–Rabbi Adin Steinsaltz
From The Strife of the Spirit, “Destruction and Redemption,” p. 17 by Rabbi Adin Steinsaltz