Complex sentence: His first work in this period was "Edifying Discourses in Diverse Spirits", which included "Purity of Heart is to Will One Thing", and "Works of Love", both authored under his own name.
Split into simpler sentences: His first work in this period was "Edifying Discourses in Diverse Spirits", which included "Purity of Heart is to Will One Thing". That book along with "Works of Love" were both authored under his own name.