Doubting by Alister McGrath
An excellent, short book on doubt, deals with this issue in a useful and pastoral way. Especially good suggestions for students and scholars confronted with challenges. It concentrates on approaches to questions more than answers for questions.
This book is the memoir of a young Christian wrestling with the meaning and implications of Christian faith. It is well written and easy to read, with a thread of encouragement for the future. The issues that trouble Rachel include science and evolution, but the more important issues deal with hell and judgment.