The book was written by His Holiness long before he entered monasticism, when he was an active Sunday School teacher. It is his first spiritual book, or publication, and I am not sure it was edited a lot afterwards. I absolutely loved it, but I must say that the English version is poorly translated and does not reflect the richness and spirituality of this book. But it introduced H.H. to the Coptic community.
Some of the books of H.H. are compilations of his weekly lecture, Wednesday's in the Grand Cathedral in Cairo or in the Theology School.