Is it just a coincidence that the dominant story line we find in the Church today is one where God is furious with the created realm, places higher value on right thinking and belief over right action and living (we are saved, so the story goes, by getting our thinking right about God, irrespective of whether or not our physical lives change), where sharing the gospel is reduced to ideas and mental consent,
There are several things that make for sure signs of a cults, things that all pseudo-christian cults have in common. One of those is this--Christianity makes salvation far too easy, so they feel the need to add to it. For them, it is not hard enough to say that the defining attribute of a Believer is that they believe. They must also act. But it is not enough that they simply act, they must also act in ways that the cult leaders approve of, they must hold opinions that the cult leaders claim are right, and not question them lest they be cast into the outer darkness of those unenlightened.
So, for this particular blogger, for someone to say that they believe the Gospel is not enough--they have to act as if they do. It is, in essence, adding law to the Gospel. I do not say "the Law", but it is a law, one that he and other Emergents have made for themselves, and insist on others follow.
Of course, it is a complex situation. We know that simply saying the one believes God exists is not enough, "the devils also believe, and fear". The demons know very well that God exists, and rather than that knowledge leading to their salvation, it only adds to the certainty of their own damnation.
Yet the truth is, when it comes to salvations, belief is essential. "Believe on the Lord Jesus Christ, and you will be saved", "Repent, and believe the Gospel". The mental consent this blogger derides and ridicules is one of the essential first steps.