Three and only three of the Sacraments each imprints on the soul an indelible character, which is never removed. Neither great sin, nor great virtues, nor sincere prayer, nor apostasy, heresy, or schism, nor even condemnation to Hell can ever remove any of these indelible characters.
Catechism of the Catholic Church: “698 The seal is a symbol close to that of anointing. ‘The Father has set his seal’ on Christ and also seals us in him. Because this seal indicates the indelible effect of the anointing with the Holy Spirit in the sacraments of Baptism, Confirmation, and Holy Orders, the image of the seal (sphragis) has been used in some theological traditions to express the indelible ‘character’ imprinted by these three unrepeatable sacraments.”
The above teaching is dogmatic. But next I will offer my speculative theology on these indelible characters.
These three Sacraments, and therefore also their indelible characters, are a reflection of the most holy Trinity. Baptism is the primary Sacrament; no other Sacrament precedes it. So Baptism is a reflection of the Father, who does not proceed. Confirmation is a strengthening of Baptism; the one Sacrament proceeds directly and solely from the other. So Confirmation is a reflection of the Son, who proceeds solely from the Father. Holy Orders requires both Baptism and Confirmation; an ordained person must be both a baptized Christian and a confirmed (spiritually mature) Christian. So Orders is a reflection of the Holy Spirit, who proceeds from the Father and the Son.
When we say that each of these three Sacraments imprints an indelible character, we are using an analogy. The soul is not physical, so it cannot have a physical character (letter or symbol) printed upon it. However, it is an apt analogy. The soul is in some way changed, in addition to the grace that is given (and perhaps lost by grave sin). The soul is in some way different from those souls that lack the formal Sacrament of Baptism, the Sacrament of Confirmation, and the Sacrament of Holy Orders.
Continuing the analogy, these three characters, in someone who has all three, are not entirely separate. If we consider each as if it were a printed symbol, they would be interlocked in some way, and not entirely separate. For these three Sacraments are interrelated. More importantly, these three Sacraments are a reflection of the Trinity, of our God who is Three yet One. So a priest who has all three characters has all three symbols, but they are in some sense three yet one.
Next, I must ask whether the indelible character of ordination is different in a deacon, as compared to a priest, as compared to a bishop. Since the character represents the Sacrament, each character for the three Sacraments must be different in some way. But the same reasoning applies to the single character for holy Orders. Since a deacon is fundamentally different from a priest, and a priest fundamentally different from a bishop, it makes sense that the character differs.
What happens, then, if a man is ordained a deacon, then becomes a priest, then a bishop? The Sacrament of Ordination can only be received once, but it can be received in three degrees (deacon, priest, bishop). So this Sacrament is itself like the Trinity: three yet one. And all this implies that the character is one, yet it changes in some way with each degree. The indelible character of Ordination is different in a deacon, as compared to a priest, as compared to a bishop.
Notice how the many gifts we receive from God are a reflection of God, who is three yet one.
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