We say that the Sacred Heart of Jesus is the full Jesus. His heart is not just some part of him. All of Jesus is contained in his heart. We never say that this also can be applied to us. If a doctor removes my heart that heart is not me anymore (although there are strange stories from those who received a new heart). This is just confusing. Am I the only person to ask such a strange question? Are there any theological writings on this issue?
Well we are not the same as Jesus, so our heart wouldn’t contain our whole essence. I think our individual parts can contain some essence though. I have read how someone getting an organ transplant ended up having some personality traits of the donor. It is possible that the whole body together with the spirit makes up the person as we know it. This explains why a brain transplant can never work. The person is more than the brain; the person is everything combined.
The Catholic Encyclopedia has a pretty good article on it:
Note that the word “heart” is used in different ways. If we get to the heart of a matter, we reach its essence or cause. Similarly, a person’s heart (not just Christ’s) is more than the heart of flesh. The physical heart is, however, a symbol of the inmost spiritual faculties, of the will, conscience, desires, etc.; and particularly of love (both in a theological sense and in the sense of an emotion).
Among physical human hearts, Christ’s is unique in that it is, as part of the body, hypostatically united to the Eternal Word, as is every other part of his sacred humanity. It receives special devotion because it is a symbol of his love.
Jesus’s soul is glorified, in fact the hypostic union means it is at the highest state of glorification.
Therrfore I believe that His soul is plenipotent, that is, that it is such that every part of it has the power of creating any part of His Body. And sustaining it as a Living part of His Body.
In fact that’s how I believe His Body and Blood are made present in the Eucharist. When His soul is united with the matter of the Bread and Wine, the Bread and Wine, which is only a particular form of non-living matter, by being given life, no longer exists. Instead every particle of it is united with the plenipotental soul of Jesus and thus every particle is then every part of Jesus.
In his encyclical Misrentissimus Redemptor, Pope Pius XI stated:
“the spirit of expiation or reparation has always had the first and foremost place in the worship given to the Most Sacred Heart of Jesus”.
I think it’s simply a reference referring to Jesus’ divine love and mercy. To me, I take such remarks as I do things like “He has the whole world in His hands” (really?) and that Mary will ultimately “crush the head of the snake”. They are written figuratively—not literally—to get an idea across.
Any part of Jesus is all of Jesus. Jesus (in his glorified form) cannot be subdivided.
It’s the same reason why, if a Host is broken and you receive half, you still receive all of Jesus. You can’t receive “half of” Jesus. Likewise, consuming two Hosts won’t give you “more” Jesus.