Complex sentence: The 1484 Synod of Constantinople was the first synod to condemn the Council of Florence, as the so-called "1450 Synod of Saint Sophia" never took place and its documents are a forgery of the early 17th century.
Split into simpler sentences: The 1484 Synod of Constantinople was the first synod to condemn the Council of Florence. The so-called "1450 Synod of Saint Sophia" never took place and its documents are a forgery of the early 17th century.