I and the Father are one.
The Son as Son, and insofar as he is Son, does not proceed in any way from himself and so is completely one with the Father; since he is nothing beside him, claims no special position of his own, confronts the father with nothing belonging only to him, makes no reservation for what is specifically his own, therefore he is completely equal to the Father. The logic is compelling: If there is nothing in which he is just he, no kind of fenced-off private ground, then he coincides with the Father, is “one” with him. It is precisely this totality of interplay, that the word “Son” aims at expressing. To John, “Son” means being from another; thus, with this word he defines the being of this man as being from another and for others, as a being that is completely open on both sides, knows no reserved area of a mere “I”. When it thus becomes clear that the being of Jesus as Christ is a completely open being, a being “from” and “toward”, which nowhere clings to itself and nowhere stands on its own, then it is also clear at the same time that this being is pure relation (not substantiality) and, as pure relation, pure unity.
(pp 185 -187)
My teaching is not mine, but his who sent me (7:16). What, then, is the teaching of Jesus that is simultaneously his and not his? Jesus is “word”, and thus it becomes clear that his teaching is he himself. If one reads the sentence again with this insight, it then says: I am by no means just I; I am not mine at all; my I is that of another. With this we have moved on out of Christology and arrived at ourselves. The most individual element in us – the only thing that belongs to us in the last analysis – our own “I”, is at the same time the least individual element of all, for it is precisely our “I” that we have neither from ourselves nor for ourselves. The “I” is simultaneously what I have completely and what least of all belongs to me. Thus here again the concept of mere substance (= what stands in itself ! ) is shattered, and it is made apparent how being that truly understands itself grasps at the same time that in being itself it does not belong to itself; that it only comes to itself by moving away from itself and finding its way back as relatedness to its true primordial state. (pp189-190)
- Joseph Ratzinger. 1969. Introduction to Christianity