Nehemiah 8:18 "The Book of the Law of God" is a document title and should be capitalized because there is no better way (yet) to graphically represent titles.
Nehemiah 9:3 "The Book of the Law of Yahweh" is a document title and should be capitalized because there is no better way (yet) to graphically represent titles.
Nehemiah 12:23 "The Book of the Annals" is a document title and should be capitalized because there is no better way (yet) to graphically represent titles.