Complex sentence: The flow of new anthems and service music slowed down but in 1883 he completed his oratorio "Mary Magdalen" which was followed in 1887 by "The Crucifixion", the work for which he is most remembered.
Split into simpler sentences: The flow of new anthems and service music slowed down, but in 1883 he completed his oratorio "Mary Magdalen". This was followed in 1887 by "The Crucifixion", the work for which he is most remembered.