written by st. francis de sales, about 400 years ago. still relevant today, and it will be relevant 10,000 years from now.
if you ever doubt the truth of your catholic faith, or if you are considering becoming catholic but aren't yet convinced that it is the church started by Jesus Christ, you must read this book. all of the modern Catholic apologists owe a lot to this one. st. francis methodically explains and defends the catholic faith against protestant attacks. absolutely brilliant.