This episode covers chapter 21 of Introduction to the Devout Life by St. Francis de Sales. Be sure to follow along in the book if you have it! You can find it anywhere fine books are sold!
Below is a link to some editions from some great publishers
https://ascensionpress.com/products/introduction-to-the-devout-life?_pos=1&_sid=b8ea883bb&_ss=r
Cor Jesu Press doesn't have Introduction to the Devout Life but they have a handful of other classics worth keeping on your shelf!
https://corjesupress.com/collections/all