Introduction to the Devout Life by St. Francis De Sales

First published in the early 17th century, it has proven its value as a daily spiritual guide and helpful reference for living an authentic Christian life. Written specifically for laymen, it began as letters from Saint Francis to a married woman who was seeking holiness amidst the distractions of her life of wealth and status. It contains treasures of wisdom for every reader, from eager beginner to lifelong Christian. Summary by Wikipedia and Phil Chenevert.