“All action that does not proceed from knowledge is lacking in principle and thus is nothing but a vain agitation; likewise, all temporal power that fails to recognize its subordination to the spiritual authority is vain and illusory: separated from its principle, it can only exert itself in a disorderly way and move inexorably to its own ruin.”
~ Rene Guénon
To state the question in its simplest form, the Church and the State represent to separate functions, these being knowledge and action. Understood in this way, it becomes blatantly obvious that there exists between the two a relationship that is not “separate but equal,” but rather “hierarchical.” This is because human action must proceed from knowledge. Knowledge, for rational beings, is the principle of their action in the physical world.
Now clearly one could respond that “action” takes place all the time, through the growth of plant life, for example, that has no origin in thought. This objection can be answered by taking a more comprehensive view of reality.
According to the traditional understanding of the cosmos, all beings are “thoughts” of the Creator, and Creation is the expression through act of the Mind of God. And so, from this point of view, the existence of the world itself has its origin in thought, which is to say in the “knowledge” of God. This is why Christianity says of Christ, the Logos, that “through him all things were made.” Because Christ is the “Word” of God, he is the mind of God expressed through existence, and hence it can be said that he is “the Lamb of God sacrificed from the beginning of the World.” This is the relationship between knowledge and action in terms of the macrocosm.
Man, for his own part, is called a “microcosm,” reflecting in himself the structure of the macrocosm. Thus, while brutes (irrational animals) do indeed “act” upon the world in various ways, they do not participate in rationality. The knowledge from which their activity proceeds has its origin in the laws of nature, to which they are passive. Their action has its origin in knowledge, even though it is not their knowledge. That is why plants and animals, although alive and acting, do not reflect the universe in the way that man, who is the “rational animal,” contains it within himself.
Human action, if it is properly human, which is to say rational, proceeds from knowledge. Although it is possible for man to act on a brute level, and to go on living on a vegetal level, this is not human action properly speaking. All human action proceeds from knowledge, and this knowledge is found in the human being himself and is not, as was the case with the brute, a passive or “instinctual” participation.
In summary, we can say with Guénon that action without knowledge is not human, but rather an animal type of knowledge. If man does not subordinate his action to knowledge, then his action is disordered. He is acting either irrationally or “non-rationally,” and thereby degrades his action to the level of the brute.
 Spiritual Authority and Temporal Power, p. 28-29.