Abbots and Mitred Abbots, Priors

The adoption of certain episcopal insignia (pontificalia) by abbots was followed by an encroachment on episcopal functions, which had to be specially but ineffectually guarded against by the Lateran council, AD 1123.

It has been maintained that the right to wear mitres was sometimes granted by the popes to abbots before the 11th century, but the documents on which this claim is based are not genuine (J. Braun, Liturgische Gewandung, p. 453). The first undoubted instance is the bull by which Alexander II in 1063 which granted the use of the mitre to Egelsinus, abbot of the monastery of St Augustine at Canterbury. The mitred abbots in England were those of Abingdon, St Alban's, Bardney, Battle, Bury St Edmunds, St Augustine's Canterbury, Colchester, Croyland, Evesham, Glastonbury, Gloucester,St Benet's Hulme, Hyde, Malmesbury, Peterborough, Ramsey, Reading, Selby, Shrewsbury, Tavistock, Thorney, Westminster, Winchcombe, and St Mary's York. Of these the precedence was originally yielded to the abbot of Glastonbury, until in AD 1154 Adrian IV (Nicholas Breakspear) granted it to the abbot of St Alban's, in which monastery he had been brought up. Next after the abbot of St Alban's ranked the abbot of Westminster and then Ramsey. Elsewhere, the mitred abbots that sat in the Estates of Scotland were of Arbroath, Cambuskenneth, Coupar An, Dunfermline, Holyrood, Iona, Kelso, Kilwinning, Kinloss, Lindores, Paisley, Melrose, Scone, St Andrews Priory and Sweetheart. To distinguish abbots from bishops, it was ordained that their mitre should be made of less costly materials, and should not be ornamented with gold, a rule which was soon entirely disregarded, and that the crook of their pastoral staff (the crosier) should turn inwards instead of outwards, indicating that their jurisdiction was limited to their own house.

Extract from:

http://en.wikipedia.org/wiki/Abbot

The word abbot, meaning father, is a title given to the head of a monastery.

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Abbots more and more assumed almost episcopal state, and in defiance of the prohibition of early councils and the protests of St Bernard and others, adopted the episcopal insignia of mitre, ring, gloves and sandals.

Main article: Mitres

It has been maintained that the right to wear mitres was sometimes granted by the popes to abbots before the 11th century, but the documents on which this claim is based are not genuine (J. Braun, Liturgische Gewandung, p. 453). The first undoubted instance is the bull by which Alexander II in 1063 granted the use of the mitre to Egelsinus, abbot of the monastery of St Augustine at Canterbury. The mitred abbots in England were those of Abingdon, St Alban's, Bardney, Battle, Bury St Edmunds, St Augustine's Canterbury, Colchester, Croyland, Evesham, Glastonbury, Gloucester, St Benet's Hulme, Hyde, Malmesbury, Peterborough, Ramsey, Reading, Selby, Shrewsbury, Tavistock, Thorney, Westminster, Winchcombe, and St Mary's York. Of these the precedence was originally yielded to the abbot of Glastonbury, until in AD 1154 Adrian IV (Nicholas Breakspear) granted it to the abbot of St Alban's, in which monastery he had been brought up. Next after the abbot of St Alban's ranked the abbot of Westminster and then Ramsey. To distinguish abbots from bishops, it was ordained that their mitre should be made of less costly materials, and should not be ornamented with gold, a rule which was soon entirely disregarded, and that the crook of their pastoral staff (the crosier) should turn inwards instead of outwards, indicating that their jurisdiction was limited to their own house.

The adoption of certain episcopal insignia (pontificalia) by abbots was followed by an encroachment on episcopal functions, which had to be specially but ineffectually guarded against by the Lateran council, AD 1123. In the East abbots, if in priests' orders and with the consent of the bishop, were, as we have seen, permitted by the second Nicene council, AD 787, to confer the tonsure and admit to the order of reader; but gradually abbots, in the West also, advanced higher claims, until we find them in AD 1489 permitted by Innocent IV to confer both the subdiaconate and diaconate. Of course, they always and everywhere had the power of admitting their own monks and vesting them with the religious habit.

The power of the abbot was paternal but absolute, limited, however, by the canon law. One of the main goals of monasticism was the purgation of self and selfishness, and obedience was seen as a path to that perfection. It was sacred duty to execute the abbot's orders, and even to act without his orders was sometimes considered a transgression.

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Prior
Priory

http://www.newadvent.org/cathen/01015c.htm

In England the pontifical insignia were assigned first to the Abbot of St. Augustine's, Canterbury, in 1063 and nearly a hundred years later to the Abbot of St. Alban's. The privilege was gradually extended to other abbeys until, at the close of the Middle Ages, every monastic house of importance in Europe was presided over by a mitred Abbot. 

References


Oestereich, T. (1907). Abbot. In The Catholic Encyclopedia. New York: Robert Appleton Company. Retrieved October 20, 2013 from New Advent: 
http://www.newadvent.org/cathen/01015c.htm

Society for the Diffusion of Useful Knowledge (1833). The Penny Cyclopaedia of the Society for the Diffusion of Useful Knowledge: A - Andes. Knight. pp. 12–.

Koopmans, R. (2016). Thomas Becket and the Royal Abbey of Reading. The English Historical Review, 131(548), 1-30.