I have also come across some fine resources on Christian discernment I'd like to bring to your attention.
One of these is a message by John Piper which I also mentioned in yesterday's post, How I Distinguish Between the Gospel and False Gospels. it's so good that it's worth mentioning a second time.
Another conference message from Piper is titled "How Do Christians Explain Truth?".
Mark Dever has a message entitled "Discern Your Doctrine" that is available for free download.
In Rob Bell, the Pastor’s Task of Discernment, and My Heart, C. J. Mahaney presents a balanced article concerning how pastors ought to pursue their task of discernment while at the same time maintaining a watchful, humble eye on their own hearts, praying for those whose errors they expose, and making sure to keep preaching sound doctrine, and not just continually point out error. I would think that his admonitions are suitable not only for those in those in pastoral ministry, but also for all Christians called to proclaim their faith.
How blessed we are to have such great teaching resources available to us through the Web.