If, however, you are fulfilling the royal law, according to the scripture, "You shall love your neighbor as yourself," you are doing well.  But if you show partiality, you are committing sin and are convicted by the law as transgressors.  For whoever keeps the whole law and yet stumbles in one point, he has become guilty of all.  For He who said, "Do not commit adultery," also said, "Do not commit murder."  Now if you do not commit adultery but you do commit murder, you have become a transgressor of the law.

James writes about the difficulty of keeping the law.  He tells us that if we stumble at even one point, we become "law-breakers".  What I find most interesting about this section of James' epistle is the constant pointing to Jesus.  James tells us about a "royal law".  This law is, "You shall love your neighbor as yourself."  It is royal, simply because a King gave us this law.  Jesus.

Next, James writes about another law.  "He who said... also said..."  Again, James is pointing to Jesus.

Often we try to separate Jesus from the law.  We believe that Jesus the grace-giver supersedes the law of Moses.  James purposefully joins the two.  He knows that the One who initiates the law is the only One who can satisfy it.

Why do you think James speaks so vehemently about partiality?
What did Jesus say about His role with the law?