For the next seven months, however, Venice will find itself in the middle of the roiling debate about Islam’s place in Europe. On Friday, as part of the Venice Biennale, a former Catholic church in the Cannaregio neighborhood will open its doors as a functioning mosque, its Baroque walls adorned with Arabic script, its floor covered with a prayer rug angled toward Mecca and its crucifix mosaics hidden behind a towering mihrab, or prayer niche.
