S.M. Miranda, Catholic layman who has dedicated a website to the evangelization of the Catholic faith in defense against modern skepticism, heresy and unbelief, has presciently written:
The Church has always been beset by evil and false teachings for as long as she has existed. There are three main reasons why division and discord have always threatened (but never sapped) the foundation of the Church. The first and primary reason is that the Church stands as a lamp set on a hill for all to see and hear. She proclaims the message of her master, Our Lord Jesus Christ, and condemns the evils of the world while offering healing and forgiveness to all evildoers. The visible Church’s mission of healing and teaching does not go unnoticed by the Prince of this world: the devil. The Catholic Church stands as the ark of salvation and a very real threat to his domain. Hence the devil attempts every kind of attack on the Church by use of external forces (violence, persecutions, and natural disasters) along with internal discord (heresies, schisms, apostasy, and temptation of the clergy and laity). If not for Our Lord’s guarantee that the Church would never fail (Matthew 16:18), there is no way the Church’s members and hierarchy could resist the devil perpetually. The second reason heresy and discord are always found within the Church, is that certain men find the teachings and expectations of the Church burdensome. Very often, these men find that doing the right and moral thing is painful and often requires much suffering. It seems easier for many people to either ignore part or all of the Church’s teachings or substitute doctrines into the Faith that are more to their liking. Finally, the Church has always been assailed by heresy because men have often had a hard time accepting the limitations of their own nature. Pride often besets men (especially scholars and philosophers) and convinces them that they have no intellectual limitations. The result of intellectual pride is a continuous attempt to rationalize the mysteries of God. Some things (such as understanding the true nature of the Trinity) are beyond the nature of man’s intelligence. But because prideful men cannot accept that the nature and acts of the infinite God are beyond the reach of men, these philosophers either reject God or rationalize the faith to fit their human philosophies. In the end, a fully rationalized faith has no room for miracles, the divinity of Christ or many other core tenets of the Faith. What results from undue rationalizations are nothing less than heresies and a watered down faith. Thus the attacks of Satan, man’s dislike of the moral life, and prideful rationalizations of Christian mysteries account for the continuing presence of false teaching in a world that has been given a divinely instituted and visible teaching Church.