If there was going to be a great deception in the church, a "falling away," what would it look like? Jesus said that "if it were possible, even the elect would be deceived."
Here are some characteristics we should expect:
This deception would tell people to expect a great revival, instead of expecting a great falling away (like the Bible teaches).
This deception would be close to the real thing, because good counterfeits are hard to distinguish from the original. In order to deceive effectively, the deception will claim to be "all about Jesus."
This deception would have to be embraced by the majority, because people usually go along with the majority.
This deception would use the Bible to discredit what the Bible actually teaches. An attack from outside the Bible would be too obvious. When scripture itself is twisted and distorted it is extremely useful in deceiving people.
This deception could only happen if Christians were being taught to somehow let down their guard. The Bible is full of warnings against falling away and tells us to avoid false teachers and false doctrine, so some other beliefs would have to be repeatedly instilled into people's minds in order for them to ignore the Bible.
This deception would have to grow not by bringing pagan ideas into the church from pagans, but from trusted Christian leaders. These trusted leaders could have their trust created and propped up artificially by marketing and repeated exposure, in the same way that large corporations create trust through relentless advertising.
This deception would have leaders who are guilty of major moral failings, greed, dishonesty and/or an ability to twist the Bible. These leaders would have to prop each other up in order to appear like a unified group of highly respected spiritual champions; they would spend a lot of time and energy convincing their followers of how great (and humble) they are. Here's an advertisement in Christianity Today magazine that tells readers who they can trust (because an advertisement wouldn't lie, right?)...
This deception would flourish if people were taught that the "mind/intellect is bad, but the spirit is good." This false dichotomy would make people comfortable in their ignorance of Christian history, theology and even the Bible itself. But their reliance on emotional experiences and feelings would ensure a constant state of delusion and/or reliance on manipulative leaders.