Answer
The book of Genesis describes the origins of the universe, humanity, sin, and redemption. Its iconic stories include God’s creation of the world, Adam and Eve’s fall into sin, the global flood in Noah’s lifetime, and the establishment and growth of the nation of Israel. The best evidence indicates that Moses wrote Genesis between 1440 and 1400 BC, during the 40-year period after Israel’s exodus from Egypt and before the nation entered the Promised Land.
Identifying the author of Genesis is key to determining when the book was written, as it narrows the period of time to the writer’s lifespan. Thus, although Genesis is technically anonymous, as the writer doesn’t identify himself in the text, the Bible assigns authorship of Genesis to Moses (e.g., Malachi 4:4; Matthew 8:4). Moreover, when citing events in Genesis, Jesus refers to Moses as the book’s author (Matthew 19:4–6; Mark 12:26; Luke 16:29; John 7:22), as does the apostle Paul (Romans 10:19; 1 Corinthians 9:9).
Furthermore, the Bible provides historical details that shed light on when Moses wrote Genesis. For instance, Deuteronomy 34:7 says Moses died at the age of 120, shortly before Israel entered the Promised Land: “Moses was 120 years old when he died. His eye was undimmed, and his vigor unabated” (ESV). Israel entered the Promised Land around 1400 BC, indicating Moses was born about 1520 BC. Therefore, he wrote Genesis between 1520 and 1400 BC.
However, when Moses wrote Genesis can be further pinpointed because the Bible says that he started to record Israel’s history during the last 40 years of his life. God first instructed Moses to write after Israel escaped from slavery in Egypt and fled into the Sinai Peninsula through the parted Red Sea (Exodus 17:14; cf. Numbers 33:2). The exodus occurred around 1440 BC; then Israel wandered in the desert for 40 years before finally entering the Promised Land about 1400 BC. Moses died just before Israel entered the Promised Land (Deuteronomy 34:1–7).
The primary objection to Moses’ authorship of Genesis is called the documentary hypothesis, which arose in the context of liberal theology in 19th-century Europe. Its leading figure, Julius Wellhausen (1844—1918), argued that Genesis has four authors—none of whom is Moses—and he abbreviated them J, E, P, and D. J stood for the Yahwist, who called God YHWH; E stood for the Elohist, who called Him “Elohim”; P stood for the Priestly source, primarily associated with the book of Leviticus; and D stood for the Deuteronomist, primarily associated with the book of Deuteronomy. According to the hypothesis, all four authors contributed and edited portions of Genesis. Wellhausen taught that the earliest sections of Genesis date to around 800 BC, and the latest sections to around 600 BC—centuries after Moses’ lifetime. Although Wellhausen’s theories have persuaded some, those who believe in the divine inspiration and inerrancy of Scripture still affirm the biblical witness of Moses’ authorship of Genesis.
Jewish tradition has attested to Moses’ authorship of Genesis for nearly 3,500 years, starting with his successor, Joshua (e.g., Joshua 8:31). Christian tradition has held to it for over 2,000 years, beginning with the New Testament (e.g., Luke 24:27, 44; John 5:46; Acts 15:1; 2 Corinthians 3:15). Arguments that reject Moses’ authorship of Genesis—disputing the testimony of biblical figures from Joshua to Jesus—lack evidence and expose the anti-supernatural presuppositions of its proponents. For those who believe that God divinely inspired the authors of Scripture, there is no reason to doubt the Bible’s straightforward teaching that Moses wrote Genesis.
