The entire block was seminary buildings around a courtyard. What I believe happened is that the seminary leased out a part of their property for construction of the apartment tower so they now have guaranteed income from the lessees, but that necessitated demolishing part of one of their existing buildings.

Not far away, the Cathedral of St. John the Divine leased out part of their property during the past 15 years for construction of three apartment buildings. But in that case the only demolition that happened was of a stonecrafters' shed and no actual religious/instructional buildings were touched.