A canon regular is a member of the clergy of the Catholic Church who has vowed himself to the service of a particular church along with other clergy with whom he lives a common, religious life of poverty, chastity, and obedience in a clerical monastery attached to this church under the authority of a prelate and superiors. This formal description is only a way of saying that a canon regular is a priest or deacon who seeks to live a life in imitation of the apostles, in the service of the Word of God and of the altar, holding no personal property of his own, but rather living a common life under a priestly superior.
From the beginning of the Christian Church the life of the clergy was always measured by high expectations of virtue in faithfulness to authentic teaching and simplicity of life. In the New Testament we can see the development of formal clerical discipline beginning gradually in Acts and in the epistles of St. Paul. In the early church councils, for example in the Council of Nicaea (A.D. 325) the bishops of the ancient church were eager to establish norms for the life and conduct of the clergy. In the ancient church of the 4th and 5th centuries there was a wonderful flourishing of fervent clerical life in the dioceses of Southern France, Italy, and North Africa under the leadership of such great fathers of the Church as St. Ambrose of Milan, St. Augustine of Hippo, and St. Paulinus of Nola. The diocesan clergy lived then a common, monastic life with their bishops. These clerics were inscribed in the list or kanon – a Greek word meaning “rule” – of clergy of their dioceses, and so were called “canons” or canonici. Of course this ideal was not easy to retain, and so over time there crept in the abuses in clerical life of concubinage and independent living with the scandals and disedification of the faithful which followed. Vigorous reforms were undertaken at the time of the emperor Charlemagne (A.D. 800), but the greatest was under Pope St. Gregory VII in the 11th century. This great pope called for a renewal of the life of the clergy with celibacy and poverty and common life. The implementation of this “Gregorian” reform led to the foundation of many religious communities in the 12th and 13th centuries. In St. Gregory’s mind the life of a canon regular was simply the life meant for any diocesan priest, and the various orders of canons regular (among them, of course the Norbertines) are simply the survival of this original ideal of clerical community and worship without personal property in imitation of the Lord’s Apostles.