Since the relation of the ego to the self is like that of the son to the father, we can say that when the self calls on us to sacrifice ourselves, it is really carrying out the sacrificial act on itself.
We know, more or less, what this act means to us, but what it means to the self is not so clear.
As the self can only be comprehended by us in particular acts, but remains concealed from us as a whole because it is more comprehensive than we are, all we can do is draw conclusions from the little of the self that we can experience.
We have seen that a sacrifice only takes place when we feel the self actually carrying it out in ourselves.
We may also venture to surmise that insofar as the self stands to us in the relation of father to son, the self in some sort feels our sacrifice as a sacrifice of itself.
From that sacrifice we gain ourselves – our “self” – for we have only what we give.
But what does the self gain?
We see it entering into manifestation, freeing itself from unconscious projection, and as it grips us, entering into our lives and so passing from unconsciousness into consciousness, from potentiality into actuality.
What it is in the diffuse unconscious state we do not know; we only know that in becoming our self it has become human. ~Carl Jung; “Transformation Symbolism in the Mass”; CW 11, par. 398