Karl Rahner, The Trinity, Crossroads Publishing, 1970, pp. xxi + 122. Link to purchase here.
Before I get too far ahead of myself, the book begins with realizing the modern problem of the Trinity. Most Christians do not even know what it is, nor think the doctrine has any bearing on their life. Rahner points out that it doesn’t matter to most whether or not the Son was incarnate, what really matters is that God became incarnate, irrespective of which divine person did so (could just as easily have been the Father or Spirit). As well as, “Should the doctrine of the Trinity be dropped as false, the major part of religious literature could well remain unchanged” (and may I add, the majority of sermons and prayers). We further don’t have a trinitarian view of grace because all that matters is that “God” gives us grace.
The Trinity seems outdated and unrelated to our lives in any way. It is a doctrine we may confess, but most Christians could not claim to actually believe it with an fervency as it has virtually no relation to them at all. It’s just an abstract, incomprehensible concept. This is the stage Rahner sets for this short book. It comes from a desire to re-position the Trinity in the forefront of Christian thought as who God is. If God IS Trinity, then an understanding of this is absolutely necessary if Christians are to know anything about grace and Christ, or be able to relate to God in a substantial way (though it could come from experience and not a dense theological treatise!). Now, back to a few preliminary remarks.
For those of you who do not know, Karl Rahner was a Roman Catholic theologian who lived 1904-84, who was arguably the most influential Catholic theologian of the 20th century. That’s a pretty big deal. His writings grew in stature immediately following the Second Vatican Council of the Roman Catholic Church. Biographical information aside, I read this book rather quickly (its only 120 pages in length) because I was fascinated in the topic, the Trinity.
This work has a reputation of being one of the groundbreaking works in modern Trinitarian thought. Though short, and simply titled, this book is not meant as an introductory textbook to the Trinity. Its audience is one already grounded in the historical formulations of the Trinity as well as the lingering controversies. As such, there were points which I had trouble understanding completely. Karl Rahner is notorious for writing extremely dense prose and using abstract philosophical language. Add all of that on top of the fact that it is some of the first real Catholic theology I’ve read, with its distinctive terms and ideas apart from my Protestant tradition, and it was definitely a harder read than the 120 pages gives away at first.
Nonetheless, I came away with a wonderful picture of God based upon the revelation of scripture and the preaching of the Church. This book is significant theologically for two reasons. First, Rahner develops an axiom that is now famous in Trinitarian thought (the idea was around beforehand, but he was the first to give it substantial treatment) which is “The economic Trinity (God as revealed to us) is the Immanent Trinity (God as God is within Godself eternally) and the Immanent Trinity is the Economic Trinity” (parenthetical remarks my own). Now, if you’re unfamiliar with the issues, this point may be hard to grasp, but Rahner spends 3/4 of his book developing and defending that axiom. That there may be a difference between the two, is based upon the fact that our capacity to receive revelation is limited, so God is usually spoken of as “stooping down” to our own level of understanding to reveal Godself to us in a way that is different from God eternally but still faithful to God’s identity.
Regardless, Rahner’s axiom is a very controversial claim even to this day in theology. I’ll leave you to read up on the controversy yourself some more! It basically boils down to the idea that God reveals just who God is in the events of salvation. The revelation of Father, Son, and Spirit as they are revealed in scripture and in our own experience by God just is God. God doesn’t use intermediaries to relate to us, but relates as Godself, in Trinity directly to us.
Secondly, Rahner suggests a new way of defining the threeness of God as Trinity. Church doctrine and conciliar statements usually explain the Trinity as “One substance (God) in three persons” or something similar. However, Rahner recognizes that our modern usage of the term “person” suggests something entirely different (a center of activity, consciousness, separate essence) than what is meant by the Trinitarian definition. Of course, one must be familiar with the controversy and the nature of theological concepts in order to really appreciate what is going on here. He suggests instead of using the term “person,” that we use the phrase “distinct manner of subsisting.” In this way, it does not connote tritheism, but gets at both the unity and distinction within God’s revelation to us, and as God is within Godself. Much more could be said about this, and the Trinity in general, but this brief review must suffice for now.
Though it was a very difficult book to comprehend, I can honestly say that I came away extremely enriched spiritually as Rahner explained the Trinity. It is definitely not a book for the beginner, as it would likely only further confuse one’s understanding of God if not carefully grounded in basic trinitarian doctrine beforehand. Even so, I will definitely be keeping this book on my shelf and referencing as well as interacting with Rahner’s thoughts on the Trinity for many years to come.