It has been happening through the ages, since Christ instituted His church on this planet. Churches once filled with the righteousness of Christ Himself start moving in the direction of unrighteousness. The scary thing is that these churches do not even know that they are moving away from the righteousness in action that Christ expects of them. They will vehemently deny that this skid is happening, to their own detriment. The thing about cancer is that it needs to be detected early for a good success rate in fighting it. Deny its existence and cancer will take your life. It is like putting a frog in cold water and slowly turning up the heat. Without knowing it the frog will be boiled to death. So it is with any church that denies that skid on the icy surface towards unrighteousness.
Some churches that started off well, mixed their doctrine with false doctrine. This mixture of good and false doctrine creates a poison that works very quickly through a group of people if no one recognises it and stands up against it. It creates a mutant more dangerous and destructive than even Godzilla. In the end, this church is no longer a Christian church, but merely an institution that mixed its own unbiblical anti-Christian ideas with that of the Bible, but still wanting to be called "Christian." This is clearly a synergistic type of belief which is very prevalent in Africa, where Christian beliefs have been mixed with their ancestor worship. In essence, this can no longer be called "Christian." This includes the largest "christian" church in the world today!
Other churches, while keeping a check on their doctrine, go into practices that are dubious. Things like the shepherding crisis of the late 70s and 80s. In those days, many so-called men of God started a shepherding model where the church flock had to get "permission" from their pastors to go ahead with moving house or changing jobs, etc. People no longer learnt wisdom from God through ardent study of God's Word, they became dependent on their "shepherds" for guidance in this world. In many cases this took on awesome proportions which led to many cult-like activities. Other churches would go overboard on issues like tithing to the church. They would make their people feel like second-hand citizens of heaven if they did not pay their tithes to the church.
I have recently heard of a local mega church close by where the pastors are not always treated like the shepherds of the flock. All the pastors are required to pay tithes to the church. However, the way that it was done before was to subtract the tithes from the salary before taxing was applied (pre-tax tithing). Then they heard that another church was being audited and for some "reason" decided to change the salary structures to include the tithe in the salary, let the pastor be taxed normally, and then the pastor could pay the tithes to the church himself. However, now that the tithes have been added back to the pastors' salaries, some of them have moved into the next tax bracket on the tax scale, and now actually get out less than they did before. Some as much as R250 (South African Rand)! The church should cover that loss for the pastors. This with support staff that outnumber the pastoral staff by far. In a church where there are 6000+ members, there are only 11 shepherding pastors. That is an average of 545 members per pastor! In a church where shepherding is hailed as the reason for the church's existence, I am surprised that the pastor/member ratio is so bad! There is no way that such a pastor can actually get to shepherd his flock and even get to know them! These same pastors also have to attend meetings upon meetings, leaving them with precious little time for member visitation. When a church loses its focus from shepherding its flock to running like a business, the people will suffer. Somewhere there is something wrong! Why suddenly change salary structures to avoid being caught by auditors? Is something unrighteous going on?
If the church cannot be the best example of righteous behaviour and how to treat its pastors ("managers") with respect and dignity, why should we expect it from secular businesses? Should we not then expect businesses to fail morally? How can we expect the world around us to walk on the moral high ground with regards to itself and how it treats others when the church cannot do the same?
When the church walks away from the simple truths of the Bible and incorporates psychology, leadership seminars and the like into its daily make-up, then we can expect to find a church that is morally corrupt, since it no longer has an objective base on which to stand. Rather, it is holding onto the deadly shifting sands of the pop psychology of today and leadership teachers that find it difficult to teach the Bible, but rather need to have "cute" quips to say about how good people need to be like "eagles."
I know this is a rather cryptic blog; however, it could be put at the door of much of the modern church today!