Where did James get the idea that breaking one commandment means breaking all?

[tonychanyt]

De 27:

1 Now Moses and the elders of Israel commanded the people, saying, “Keep the whole commandment that I command you today.

The chapter ended with:

26 Cursed be anyone who does not confirm the words of this law by doing them.’

If you don't follow the whole law, you will be cursed.

Ec 12:

13 When all has been heard, the conclusion of the matter is this: Fear God and keep His commandments, because this is the **whole **duty of man. 14 For God will bring every deed into judgment, along with every hidden thing, whether good or evil.

Every deed counted.

In the NT, James knew these and wrote in Ja 2:

8 If you really fulfill the royal law stated in Scripture, “Love your neighbor as yourself,” you are doing well. 9 But if you show favoritism, you sin and are convicted by the law as transgressors.

The sin of favoritism would convict you when you tried to keep the royal law.

10 Whoever keeps the whole law but stumbles at just one point is guilty of breaking all of it.

James understood the law as a unified whole. Every deed counted.

11 For He who said, “Do not commit adultery,” also said, “Do not murder.” If you do not commit adultery, but do commit murder, you have become a lawbreaker.

If you broke one law, you were convicted as a lawbreaker/sinner.

12 Speak and act as those who are going to be judged by the law that gives freedom. 13 For judgment without mercy will be shown to anyone who has not been merciful. Mercy triumphs over judgment.

James relied on the mercy of God, not his perfect deeds.

Where did James get the idea that breaking one commandment means breaking all?

The OT painted the law as a unified whole. The bad news was that everyone was a lawbreaker in this strict sense. The good news was that God's mercy triumphed over his judgment for those who believed.