What Books Would You Recommend for a Young Adult Who Has Been Questioning His Faith and Is Just Beginning to Take His Faith Seriously?

Question from a reader:

What books would you recommend for a young adult who has been questioning his faith and is just beginning to take his faith seriously?

Answer from Randy Alcorn: 

Knowledge of the Holy by A.W. Tozer

Knowing God by J.I. Packer

The Reason for God by Tim Keller

The Case for Faith by Lee Strobel

Also, an older but outstanding book that really shaped me intellectually as a new Christian was Francis Schaeffer’s He is There and He is Not Silent.