Much has been written in recent years about the practice of a prelate modifying the design of his coat of arms when he moves from one position to another in the Church. Generally speaking I am against the practice. A coat of arms, even an assumed one, becomes a unique personal symbol and is associated with the person who bears the arms. To change the original design simply because one is taking up a new position or ministry is ill advised.
I am, of course, not referring to marshaling the personal arms with those of a jurisdiction (see, abbey, or even a parish). When a cleric is translated from one jurisdiction to another of course he will then marshal his personal arms to those of the new jurisdiction because, after all, impaling or quartering the personal arms with those of a jurisdiction is a means of displaying two or more separate coats of arms together on one shield. The arms of a diocese do not “become” part of the bishops personal coat of arms. They are displayed along with the personal arms of the incumbent during the tenure of his office as part of the overall achievement but that is all.
Rather, I am speaking of a cleric slightly modifying or even changing entirely the design on the shield of his personal coat of arms. In some cases the change is a result of unhappiness with the design originally adopted. Sometimes it is the case that a cleric is appointed to be a bishop and wishes to make use of his new coat of arms at his episcopal ordination which may be as soon as only six weeks away. So, a design is hastily adopted. later, when being translated to a new see the bishop has had time to second guess his original arms and wishes to tweak the design or even change it altogether. While this is understandable it still should be frowned upon. His new position doesn’t mean he is becoming an entirely new person.
Yet we see that this has and continues to happen. Even no less than Pope Pius XII (Eugenio Pacelli 1939-1958) bore arms that were slightly different before and after he became pope. When a bishop and cardinal his arms depicted a dove displayed (i.e. with its wings spread) holding an olive branch in its beak. This is a reference to the name Pacelli which means “peace”. The dove was perched on a trimount and sitting below the arc of a rainbow, an allusion to the story of Noah from the Scriptures.
However, after his election to the papacy there are some differences. The dove now has folded wings and sits perched on the trimount which is depicted on field and above waves of water. In addition, the rainbow is now gone. Perhaps Pius XII felt the reference to the story of Noah was redundant or superfluous? Perhaps he wished to express a global desire for peace since he was elected at a time when the world was on the brink of World War II? Perhaps he simply liked this newer design more? We shall never know yet here is a good example of arms modified when going from one position in the Church to another.