The theory that would become JEDP, began with questions of word use. Why do some passages refer to God as “God,” others as “the LORD,” and others as “Lord GOD?” Why do some passages call Moses’ mountain “Sinai” and others “Horeb?” As one sorts these things out, it becomes clear that each of the four supposed authors is distinctive not just in word use, but also in writing style, interests, beliefs, and even politics.
The writing style of the Priestly Source is so distinctive that one becomes able to recognize any sentence from this author at once. He is concerned for the supremacy of the “Priests” (male descendants of Aaron’s son Eleazer) over “Levites” (male descendants of Aaron’s other son, Ithamar). He writes in exhausting detail about the Temple — its design, construction, furnishings, activities and personnel. He loves lists.
His God is not “immanent” — intimately present to every human being — but “transcendent,” far removed from human beings. His is not a God of mercy, but of wrath.
The Priestly Source supposedly wrote portions of Genesis, portions of Exodus, the entire book of Leviticus and the entire book of Numbers. Other authors, closely allied in their interests, beliefs and politics, wrote 1 and 2 Chronicles, Ezra and Ezekiel. These authors’ writing styles are also remarkably similar. It boggles me that authors who think alike will necessarily write alike; but in this case, so it is.
Related: The Nun Study