Padstow was evidently the principal centre of Petroc's activities for there are many street names and houses with a taste of Petroc to be seen in the town. The monks of Petroc-stow acquired large amounts of land on both sides of the Camel estuary extending west as far as Portreath near Redruth, North east as far as Tintagel, and inland to Lanhydrock and Bodmin. A large part of this ground forms the Hundred of Pydar or Pydarshire, derived from Petroc-shire. The bulk of the Gotha manuscript described the numerous pilgrimages and wanderings of the saint. St. Petroc travelled to Rome and Brittany, performing many miracles and healing the sick, but it is the founding of the Priory at Bodmin, which provides us with the focal point.
The hermit St. Guron had discovered how suitable a spot Bodmin was and he established his "cell" on the site of the present Parish Church. The hermitage had all the natural advantages of a suitable position. It was near running water, there was a pool, copious water springs, and the valley, then, as now, must have been verdant and sheltered. St. Guron became the founder Of Bodmin. It is possible to see the Well of St. Guron in the grounds of the Parish Church. St. Petroc came to this hermitage, from Padstow, with three of his fellow saints, Credan, Medan and Dechan. St. Guron nobly resigned his abode and proceeded to the south coast to a spot named after him, Gorran. It was not long before St. Guron's hermitage was enlarged into a Priory of considerable size and importance. St. Petroc became the first Prior of Bodmin; and later not only the Church at Bodmin and the Church at Padstow, but a number of other Churches in Cornwall, Devon and Wales were named after him. Over the two Petrockstows, for Bodmin was at first also a Petrocstow, as well as Padstow, there have been many confusions. A Petrocstow was burned by the Danes in 981 A.D., but it is recognised as being Padstow, for the Danes pillaged and burned usually coastal places. How long Bodmin was known as Petrocstow is not certain. From old manuscripts it is evident that the name Bodmin in one or other of its variants had been in use many years before the Anglo-Saxons, and later the Normans, visited the place.
St. Petroc died at Padstow and his bones were placed in a "fair shrine" placed before the high altar in the Church which he founded. His relics and his handbell (the cimbalum) were used for ecclesiastical purposes for at least five hundred years after his death, and, moreover, they were preserved for upwards of another five hundred years, until the Reformation. It might be interesting to try to visualise what a Celtic monastery of the sixth or seventh centuries was like. It was a simple, indeed primitive, establishment and bore no resemblance to the magnificent abbeys and priories of the Middle Ages. These Celtic monasteries of the Dark Ages were usually a little church and a few huts or cells; each occupied by one brother, protected by a surrounding wall of earth. The Abbot lived like his subordinate brethren. In time the manuscripts written by these monks came to be regarded as libraries. These books were not stored away on shelves but kept in leather cases and hung on pegs around the walls. The better equipped of these monasteries became our first schools.
Bodmin seems to have flourished during the Anglo-Saxon period, and in the yeare 938 A.D., King Athelstan is recorded as having granted the lands of "Nywanton" to St. Petroc's monastery. The monastery had won royal approval by conforming to Romanized-Anglo-Saxon practices. The Cornish Church with its Celtic clergy must by that time have thoroughly adopted Roman ways. The fact that English influence was at work during the ninth, tenth and eleventh centuries, is revealed in the manumissions of slaves recorded in the Bodmin Gospels. These Bodmin Gospels, now in the British Museum, are the only books of a Cornish monastery of the Dark Ages to survive. Most of the owners of the slaves whose liberation is recorded appear to have been English, but there are some whose names were Cornish and, not all the slaves were Cornish, for some were English!