"My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. For if a man comes into your assembly with a gold ring and dressed in fine clothes, and there also comes in a poor man in dirty clothes, and you pay special attention to the one who is wearing the fine clothes, and say, 'You sit here in a good place,' and you say to the poor man, 'You stand over there, or sit down by my footstool,' have you not made distinctions among yourselves, and become judges with evil motives?" (James 2:1-4)At first blush, it's hard to understand how our faith in God has any relationship in how we show favoritism to others. I could have understood it if James had spoken of our love, our benevolence, or our deeds, but James understood that our faith includes all these things. Faith not only governs what we believe, especially what we believe towards God, but it also includes how we view, judge, and accept other people around us. To James, faith in the abstract was towards God, while faith in the practical was towards other people. We cannot hold the faith of God without it affecting our disposition towards other people. John put it this way, "If someone says, 'I love God,' and hates his brother, he is a liar; for the one who does not love his brother whom he has seen, cannot love God whom he has not seen. And this commandment we have from Him, that the one who loves God should love his brother also." (1 John 4:20-21) To James, such love towards God is inseparable from our faith towards God as expressed in love towards other people.
James warns us against becoming judges with evil motives. By judging, James is not talking about any sense of judicial judgment or judging others behavior or their "fruit" as Jesus would say, but rather judging their person; making a distinction between people based on such external factors that have no relevance upon who they really are. We can judge a drunk to be a drunk, because we can see his behavior and the destruction his behavior brings upon himself and those around him. However, we cannot judge a poor or filthy person for any moral defect or neglect in their lives. Their poverty has no bearing upon their worth as a person or their standing before the throne of God. However, when we make distinctions between people based on such external factors, we make distinctions that are groundless and frivolous.
James expressly mentions judging people based on their "face", which would include using beauty, race, nationality, and countenance as measures of merit. He also warns about judging people based on their dress which would include their economic standing, their sophistication, and their political, ecclesiastical, and social elevation. All such judging comes from "evil motives." What James means by this phrase, from the original language, is an evaluation and calculation of our mind that is harsh, harmful, hurtful, and malicious. It's not evil in the normal since, but hurtful in the practical since. Paul makes it clear that God does not judge us this way, "But glory and honor and peace to everyone who does good, to the Jew first and also to the Greek. For there is no partiality with God." (Romans 2:10-11) God receives us without partiality, and so should we do to others.
Finally, as an example, James warns us of showing partiality in our gatherings. Interestingly, the word He uses here for assembly is the Greek word for Synagogue, a term familiar to those whom he was writing to. The early church was a place of refuge where people could escape the social trappings of the world around them and find a place of mutual love and acceptance regardless of their social position, wealth, or personal beauty and perceived worthiness. It was a place where aristocrats and slaves broke bread together as they shared one bread and one life in Christ. It was a place where the rich accepted and cared for the poor and where the poor accepted and blessed the rich for their kindness. It was a place where people could once again be the family of God and where all barriers to distinction and separation were torn down and dissolved. James warns us not to let our "evil" hearts destroy that for which Jesus came to create. Let us no longer look upon people with "evil" judgments but let us accept all as being of one blood and one family in God.