If you really keep the royal law found in Scripture, “Love your neighbor as yourself,” you are doing right. But if you show favoritism, you sin and are convicted by the law as lawbreakers. For whoever keeps the whole law and yet stumbles at just one point is guilty of breaking all of it. For he who said, “You shall not commit adultery,” also said, “You shall not murder.” If you do not commit adultery but do commit murder, you have become a lawbreaker.
Speak and act as those who are going to be judged by the law that gives freedom, because judgment without mercy will be shown to anyone who has not been merciful. Mercy triumphs over judgment.
James 2:8-13 (NIV)