Five Things You Should Know About Contemplative Prayer: http://standupforthetruth.com/2013/01/5-things-you-should-know-about-contemplative-prayer/
See also: Biblegateway and the Emerging Church: http://christiandiscernment.wordpress.com/2012/11/01/biblegateway-and-the-emerging-church/
The second article in particular, gives several prominant pastors and churches who have veered over into these practices. Tim Keller’s place on this list is of interest to me, having grown up in a Presbyterian church which was a sister church to the one pastor Kellor used to lead here in Virginia for many years when I was a teen. As such I have friends who hold Pastor Keller in very high regard and whom I am pretty sure are not aware of this departure on his part into apostate doctrines. It is not just sad, but very disheartening to watch these formerly respectable leaders join the ranks of those marching in lock-step toward the coming Unified World Religion of the antichrist, their followers going over that cliff right behind them like lambs to the slaughter. I am thankful for discernment ministries that don’t hesitate to call them out by name.