“When you read a worldly magazine or newspaper, it is light and agreeable reading, you easily believe in everything in it. But if you take up a religious publication or book to read, especially one relating to church matters, or sometimes when you begin reading prayers? You feel a weight upon your heart, you are tormented by doubt and unbelief, and experience a sort of darkness and aversion. Many acknowledge this. From what does it proceed? Of course, not from the nature of the books themselves, but from the nature of the readers, from the nature of their hearts, and chiefly from the Devil, the enemy of mankind, the enemy of everything holy: ‘he takes away the word out of their hearts’ (Lk. 8:12). When we read worldly books, we do not touch him and he does not touch us. But as soon as we take up religious books, as soon as we begin to think of our amendment and salvation, then we go against him; we irritate and torment him, and therefore he attacks us and torments us on his side. What can we do? We must not throw aside the good work, the reading or prayers that are profitable to our souls, but we must patiently endure and in patience save our souls.”
St. John of Kronstadt, "My Life in Christ"