While a student in Aberdeen University, John A. Mackay became fascinated by Appearance and Reality, written by Oxford philosopher F. H. Bradley. In his own book Dr. Mackay crystalizes his lifelong reflection on the crucial issues raised by Bradley.
Christian reality, Dr. Mackay says, is haunted by the demonic shadows of appearance. In language that combines logic and poetry, he explores four central realities of the faith and the specific shadows that betray them.
The reality of God and his self-disclosure to men can turn into theologism - loyalty to ideas about God. The personal encounter between man and God is often distorted by emotionalism. The church as the community of Christ is imperiled by ecclesiastical structure. Christian obedience all too easily becomes ethicism.
The author then shows how appearance threatens the church today, particularly the Protestant denominations and the ecumenical movement. He warns that "Protestantism faces the peril of becoming Romanized at a time when Catholicism is becoming de-Romanized."
In Christian Reality and Appearance Dr. Mackay has developed a new realism - a realism that communicates with people living in a world of revolutionaries and establishment types, post-Christian theologians and concerned evangelicals, ghetto dwellers and suburban commuters.