Justin hits the nail on the head:
The most controversial part of the Elephant Room inviting T.D. Jakes to participate is not whether or not it’s permissible or advisable to have a conversation with someone who cannot affirm Trinitarian orthodoxy and who preaches a prosperity gospel.
Rather, the bigger problem (as I see it) is that James MacDonald defended the decision under the idea that the Elephant Room is all about “Getting brothers together who believe in salvation by grace alone through faith alone but normally don’t interact.” Further, their site explains that the motivation behind the Elephant Room is “a dual desire to challenge and unite this generation’s pastors.”
I could not agree more. If a pastor wants to host a forum that includes an unbeliever, there is no problem with that. And in fact, under the right circumstances, it can be quite profitable to those who see the interaction. I have in mind, for example, Doug Wilson’s many meetings with Christopher Hitchens that later appeared in the movie “Collision.” In that case, no one was ever confused about Christopher Hitchens’ standing vis a vis the truth of the gospel. The same cannot be said for the invitation to T.D. Jakes. For some people, the invitation implies that all the participants have some sort of standing as Christians and faithful pastors. Therein is the difficulty.