Genesis is the first book of the Bible and I was taught that Moses wrote it (as part of the Pentateuch—the first five books of the Christian Bible). However, being taught something, even believing something, does not necessarily make it true. So what is the evidence?
There is some evidence within the Bible itself. In the Old Testament, the law is often referred to as ‘the law of Moses.’ (Eg: Dan 9:13, Mic. 6:4) plus we read that Moses wrote down all that God told him. This does not necessarily mean he wrote the book of Genesis—he perhaps only wrote down the laws, and then passed them to the people. In the New Testament people also refer to the law of Moses, which falls into the same category. Jesus refers to ‘the book of Moses’ (Mk 12:26) and there are several places when Moses is described as having written the law. Therefore it is clear that the early church believed that the law came from Moses—but not explicitly that he wrote Genesis.
If I use a modern analogy, I can say that I tell my children Hans Christian Anderson’s story of The Ugly Duckling. Now, I have never actually read his original story (I do not read Danish) nor have I ever read a translation. But I know the story from my own childhood, and I trust that it originated with him, therefore I consider it truthful to say it is his story. I might even write it down, centuries after he died, and it would still be ‘his’ story, even if I wrote it in modern English. Of course, someone looking at my book in the year 3000 might notice it is not written in Danish, or even in English of the 1800s, and they might question whether it was really a story by Hans Christian Anderson. But I think this is an accurate description of the book. (Today, we would write a colophon, saying that the story was retold by me, and the dates, but in the ancient world, this was not a thing.)
What then do we find if we look at the writing of Genesis? We do not have any original texts, so we need to use the manuscripts that we do have. The oldest manuscripts show it was written mostly in Hebrew (just two words in Aramaic, in Gen.31:47). Like all languages, Hebrew has evolved over time, and the language is not consistent throughout. There are texts written in Archaic Biblical Hebrew, Classical Biblical Hebrew, and Late Biblical Hebrew. However, most of the texts were written in Classical Biblical Hebrew. This was used from about 9th century BCE to the 6th century BCE. Within this time frame, Classical Hebrew continued to evolve and some words began to be written in different ways. It is likely therefore that Genesis 1 (the 7 days of creation) was written later than the Eden creation story, even though it is placed first in the book.
As well as the style of language, some of the terms used also help to date the texts. For example, ‘Ur of the Chaldeans (Gen.11:28) must have been written (or added) after 700 BCE, yet the city Calah in Gen.10:12 must have been written about 880 BCE, because after 704 BCE it was part of Ninevah, not a separate place.
So what do we make of all this? And does it matter?
My view is that the best way to read Genesis is as openly as you are able, making sense of what the texts say, and asking God to reveal something to you while you read. That, I think, is how biblical texts should be read. Genesis is a place where you might encounter God.
However, from an academic point of view (which generally reveals very little of God, but is extremely interesting if you like that sort of thing!) Genesis seems to be a composite text, added to over centuries by various authors or schools of thought. Whether it began with a single author is impossible to prove. Personally, I do not like to examine the various sections in isolation, taking strands from various time periods and looking at them separately. I think they were combined for a reason, and to study them properly you need to view them within the context of the whole. But others disagree. What do you think?
Thanks for reading. I hope your day is a good one.
Take care.
Love, Anne x
My main source for facts was Ronald Hendel, ‘Historical Context’ in The Book of Genesis (Leiden: Brill, 2012) 51-82.

Thanks Anne.
It’s facinating to see that these ‘academic’ questions have gripped you.
When we write, as you do, ‘However, most of the texts were written in Classical Biblical Hebrew. This was used from about 9th century BCE to the 6th century BCE’, this easily becomes a circular argument. Almost the only Hebrew texts we have are the biblical texts, and if we want to date them by their type of Hebrew, we need to decide beforehand when that type of Hebrew was in use, which we only know from the very texts we need to date.
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