"The Imitation of Christ" by Thomas à Kempis had been on my TBR list for a long time: I kept putting off reading it because I felt intimidated; maybe I also questioned how much a book published almost 600 years ago had to tell me.
When I finally got around to tackling it, I found it surprisingly approachable and relevant to my twenty-first-century day-to-day life!
My favourite quotes from the book are:

"Dreams of happiness expected from change and different places have deceived many."

and

"Praise adds nothing to your holiness, nor does blame take anything from it."

I can definitely recommend this book to anyone, Christian or not, who wishes to reflect on their value system and live a better, more fulfilling life.