Rediscover Catholicism is the first spiritual book I read from start to finish, and I think it is one of the best works to read for people looking to jump-start their faith. Matthew Kelly's writing style makes it easy to read, the stories make it memorable, and all this is done without dumbing down any of the important topics covered. I used a couple passages from the chapter on the Sacrament of Confession as the basis for some of the articles in this app, and I think it would be very beneficial to read. Here is a link to buy the book (not sponsored, just really found the book fruitful):