Answer
Keturah was Abraham’s second wife, following the death of Sarah, his first wife (Genesis 23:2; 25:1). We know little about Keturah, other than her name and the names of the sons she bore to Abraham (Genesis 25:2; 1 Chronicles 1:32–33).
There has been some debate as to whether Keturah was Abraham’s wife or his concubine, since she is described as each in different places in Scripture. Genesis 25:1 says that Keturah was his wife; 1 Chronicles 1:32 calls her his concubine. Genesis 25:6 also implies that Keturah was a concubine. A concubine was a woman who willingly entered into an exclusive relationship with a man for the purposes of meeting his sexual needs or providing children for him (Hagar was considered a concubine of Abraham’s). The woman was often a slave or a single female without male protectors. A concubine did not have equal status as a wife, but, unlike a prostitute, she was provided for and considered the sole property of the man. Because Keturah was in a monogamous relationship with Abraham, she could properly be considered his “wife,” although she had a lesser rank than Sarah had enjoyed.
It could also be that Keturah had begun her relationship with Abraham as a concubine and was then promoted to official “wife status” after the death of Sarah. This would explain the differing biblical descriptions of her role. However, Keturah, the concubine-become-wife, is never referred to in Scripture with the same respect and honor that is given to Sarah as Abraham’s wife (1 Peter 3:6).
Keturah’s sons were Zimran, Jokshan, Medan, Midian, Ishbak, and Shuah (Genesis 25:2). The descendants of Midian (the Midianites) later become a big part of Israel’s history; in fact, Moses married a Midianite (Exodus 2:15–21). All Keturah’s sons received “gifts” from Abraham (Genesis 25:6), but none shared in the inheritance of Isaac (verse 5). Keturah’s sons became the fathers of Arabian tribes living east of Israel.