New York Pastor and best-selling author Timothy Keller has found that knowing he is mortal has transformed his prayer life along with other aspects of his life. 

In May 2020 Keller was diagnosed with stage four pancreatic cancer. Since that time he has had two years of chemotherapy and is currently participating in the immunotherapy drug trial for National Institute for Health in Bethesda, Maryland.

"My cancer is still there, pancreatic cancer can break out anytime and take you, and yet we've been able to keep it somewhat at bay for a pretty long time, and so we're very grateful," says Keller in an interview for the Unbelievable? show with Ruth Jackson and Justin Brierley.

Throughout his cancer journey, Keller has continued to preach at his church, Redeemer Presbyterian Church in New York City. In the video interview, Keller explains how he and his wife Kathy's prayer life has benefited in the past few years. 

"This is going to sound like an exaggeration. My wife and I would never want to go back to the kind of prayer life and spiritual life we had before the cancer, never. Every so often, Kathy and I will say we're having a much better life now."

While active in the faith community, Keller shares that the diagnosis has forced him to slow down in life. He says it's been good. 

"The thing I saw was that I actually was too active. And I'd been too active for too long. I'm closer to where I should've been most of my life. I'm very blessed in that my relationship with my sons are good; my sons are believers. I've got a great relationship with my wife, and that is nothing but God's grace because I was too active. I felt like everybody said, 'you have to do this for me, and OK, I have to do this for you.' It's been great to be less active."

Keller has written many books on faith and some of his best-sellers are The Prodigal God, The Meaning of Marriage, and The Reason for God.

"[Knowing] you are really are going to die changes the way you look at your time, the way you look at God, the way you look at your spouse. Everything just changes when you actually realize time is limited and I'm mortal."

Keller openly shared that having faith in God hasn't kept him from experiencing anxiety during his cancer journey. However, he has found comfort in the book of Psalms. 

"There's nothing like the Psalms to teach you," Keller says. "The way I deal with the anxiety is I keep my Psalms up, and I keep my exercise up."