Dr. Frances Renda, editor of A Call to a Deeper Love: The Family Correspondence of the Parents of Saint Therese of the Child Jesus, 1861-1885, wrote a brief and powerful reflection on the lives and marital spirituality of Louis and Zelie Martin as her introduction to that book. It reflects Dr. Renda's intimate and delicate understanding of the relationship and spirituality of Louis and Zelie and what it means not only for spouses but for all Christians. I have seen no better short introduction in English. If you have not yet treated yourself to the book, please read the introduction online courtesy of the Web site of the Archives of the Carmel of Lisieux.