An explanation for this historical phenomenon might be found in the words of Isaiah, “My House shall be called a house of prayer for all peoples” (Isa. 56:7), which reflects King Solomon’s consecration prayer for the First Temple (I Kings 8:41-43) that people from all lands would come to the sanctuary and God would hear their prayers.
This is the Sukkot spirit, since the 70 offerings of the festival were brought for the benefit of what were thought to be the 70 nations of the world (Num. 19:12-39).
The message? Jewish places of worship are not intended only for prayers for internal Jewish purposes but to help bring about the unity of all peoples.
They do not require aggressive conversionist campaigns to impose Judaism on those who do not want it, but spiritual and ethical outreach to humanity in the confident hope that the time will come when a genuine United Nations will emerge, with Jerusalem as its capital and a rebuilt Temple as its inspiration.