Heresy, being a deadly poison generated within the organism of the Church, must be ejected if she is to live and perform her task of continuing Christ's work of salvation. Each pastor in his parish, each bishop in his diocese, is in duty bound to keep the faith of his flock untainted; to the supreme pastor of all the Churches is given the office of feeding the whole Christian flock (Wilhelm). The power granted to the Catholic Church of expelling heresy is an important factor in the constitution of the Church. The power of rejecting heresy however needs to adapt into the social and political circumstances of the time. In the beginning, the Catholic Church exercises its power without an organization. The bishops were able to find heresies in their congregation and checking the progress with all its power vested upon it by the hierarchy. When a heresy gathered support and proved a danger to the Church, the bishops assembled in councils, provincial, metropolitan, national, or ecumenical to discuss the matter (Wilhelm).
In the early church, heresies were sometimes determined by a selected council of bishops, or ecumenical council, such as the First Council of Nicaea. Actually, the Catholic Church had little power to punish heretics in the early years, other than by excommunication, a spiritual punishment. Excommunication was the worst form of punishment possible because it separated the believer from the body of Christ or the Church. Excommunication, or even the threat of excommunication, was enough to convince many a heretic to renounce his views (Heresy).
In the years that followed, the Catholic Church instituted the Inquisition (Latin: Inquisitio Haereticae Pravitatis Sanctum Officium), an office of the Roman Catholic Church charged with suppressing heresy. The Inquisition was a permanent institution in the Catholic Church charged with the eradication of heresies (Inquisition). The Inquisition was active in several nations of Europe, particularly where it had fervent support from the civil authority (Heresy).
The Catholic Church however, never had executed anyone for heresy. Rather, the Church turned over heretics to the respective governments for execution. Thus making heresy a part of political self-definition and exclusion (Bambrick et al). When Constantine had taken upon himself the office of lay bishop, episcopus externus, and put the secular arm at the service of the Church, the laws against heretics became more and more rigorous. Under the purely ecclesiastical discipline no temporal punishment could be inflicted on the obstinate heretic, except the damage which might arise to his personal dignity through being deprived of all intercourse with his former brethren (Wilhelm).
Why it was not possible for the Catholic Church to stamp out heresy
During the 16th century
During the 16th century, stamping out heresy became more difficult due to varied reasons such as the Black Death, changes in the society, especially the corruption and moral decay within the Catholic Church. The 16th century is the period in which the medieval Church was defining itself and unifying its identity (Bambrick et al). The Catholic Chur