Rick Hardison of Great Crossing Baptist Church preached on James 4 on 11/2/2014 (mp3). He demonstrates "four wrong ways of judging and one right way." Many people misunderstand what James was saying in this passage (and what Jesus meant about judging others as well).
1. Don't judge with false or incomplete information. Hardison doesn't use this terminology or say "cognitive bias," but too often we err in our judgement due to the fundamental attribution error. Example: You see a woman you know from church coming home one morning in the clothes she wore last night and you assume it's a "walk of shame" when actually she's been at the hospital all night taking care of her mother, who fell and broke her hip.
2. Don't slander. Slander is the spreading of something false due to the errors made in #1 above.
3. Don't judge outsiders the same as insiders (church members). Hardison has a good summary of the importance of a biblical understanding of church membership.
4. Don't judge things that are not sin. Hardison reads from a Jerry Bridges book here. Not dressing up for church is not a sin. The Bible teaches temperance rather than abstinence from alcohol, etc. (I bet that went over real well).
One critique, I think Hardison misses that judgement also implies condemnation, contra Romans 8:1. Recently reading the book unChristian (my review) which points out that when outsiders call Christians "judgmental," they really mean "condemning." The authors point out that while Christians have an obligation to point out God's standards, that does not mean that we condemn people because all of us are saved by the grace of God alone, and there is no one who is beyond redemption. There is an air of pride that James is hitting on as well.
"What if our judgmental attitudes are just posturing to look good to other believers?" Are we trying to please God or polishing our holy credentials in front of fellow insiders?" Kinnaman writes.
Christians often forget that "God's judgments about people are perfect; ours are not."
I enjoyed this sermon, hope you do too.