How to interpret Genesis 25:1-2?

Question

In Genesis 25:1-2 we see:

"Abraham had taken another wife, whose name was Keturah. She bore him Zimran, Jokshan, Medan, Midian, Ishbak and Shuah".

But even before that in Genesis 17 it says:

'Abraham fell facedown; he laughed and said to himself, “Will a son be born to a man a hundred years old? Will Sarah bear a child at the age of ninety?” '

Then in Hebrews 11:12 we read:

"And so from this one man, and he as good as dead, came descendants as numerous as the stars in the sky and as countless as the sand on the seashore. "

If the birth of Isaac is considered a miracle when Abraham was as good as dead, how is the birth of children for him in Keturah explained? A normal reading implies that the marriage with Keturah subsequent children happens after the birth of Isaac.

_{All quotations from the NIV.}

Answer 1

There is nothing in the text that particularly indicates when the relationship to Keturah took place. The accounts we read in Genesis are not necessarily in Chronological order, and the text surrounding that bit reads more like a summary of what he had when he died rather than an account of how he came by it.

Even if the children born by her happened after the events with Sarah, there would be nothing particularly contradictory about that. If God did something to Abraham's body so that he was still able to produce children even at an advanced age, there is no reason to expect it to only work with Sarah. In fact you see the same thing happening by Haggar who also bore him a son before Sarah's womb was opened.

The miracle involved a specific promise to Abraham that he would bear children by Sarah, and whatever was done to their bodies was done to both of them, although not necessary at the same time and not necessarily for one shot.

Also note that Issac, as the child of his first wife, is treated differently than the children by Haggar and Keturah. In fact the exact nature of these relationships is not known. It was not uncommon in that culture for a man of enough means to take a second wife or have a mistress, but these texts don't exactly define what the relationship to Keturah was, although she seems to be treated as more like a concubine. In any event her children were recognized as sons of Abraham but not on the same level as Issac, who received the whole inheritance rather than the token gifts given to the other children.

Answer 2

This is easily resolved by the documentary hypothesis. Although Chapter 25 does not mention God by name, the style is that of the Elohist author, and the Elohist author continues into Chapter 26.

I don't believe this, but it is possible that there is a separate geneologist author, there are geneologies with a distinctive style. But one can assign the geneologies to E with no contradiction. The E narrative is separate from the J narrative, and identifies Ketura as Abraham's concubine. J identifies Hagar.

In Islam, Muhammed's interpretation of the passage is that Ketura is another name for Hagar. This interpretation is plausible, since the E narrative tends to have corresponding figures have somewhat different names (the most prominent example being Jethro).