Expositor's Bible Commentary Commentary James 2:10

"For whosoever shall keep the whole law, and yet stumble in one [point], he is become guilty of all." — James 2:10 (ASV)

“For” indicates that James is going to explain how an act of favoritism makes a person a “lawbreaker” (v.9). It is obvious that he has set up a hypothetical case when he speaks of someone who “keeps the whole law” except for “one point,” for in 3:2 he insists that “we all stumble in many ways.” However, for the sake of his argument, he imagines a person who “stumbles” (GK 4760) or sins at just one point. His reasoning is that to break one commandment makes a person “guilty of breaking” the whole law.