Everything Happens for a Reason by Kate Bowler tells the author's story of battling cancer.
Gates said he was inspired by the book which tackles the issue with "honesty and humour".
Bowler, a Christian mum in the USA, was just 35 years old when she was diagnosed.
The book sees her grapple with the question 'why me?'.
Writing on his blog, Gates said: "Given the topic, I wasn't surprised to find that Bowler's book is heartbreaking at times. But I didn't expect it to be funny too. Sometimes it's both in the same passage."
Other books to feature in his list of summer reads include a biography on Leonardo da Vinci and the story of the universe from creation to today.
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.