The word used in Genesis 25 is ishshah and in 1 Chronicles 1 pilegesh is the word used. Strong’s lexicon has the following to say about both words.

 

The Hebrew word "ishshah" primarily refers to a female individual, often in the context of a wife or a woman in relation to a man. It is used to denote a woman in various roles, including as a wife, mother, or female member of a community. The term emphasises relational aspects, often highlighting the role of women within family and societal structures.

 

The term "pilegesh" refers to a concubine, a woman who lives with a man but has a lower status than his wife or wives. In the context of the Hebrew Bible, a concubine was often a secondary wife, who had certain rights and responsibilities but was not on equal footing with a primary wife. The role of a concubine was primarily to bear children and provide companionship.

In ancient Near Eastern cultures, including Israel, concubinage was a socially accepted practice. Concubines were often taken by men of wealth and status, including kings and patriarchs, to ensure the continuation of their lineage and to strengthen familial alliances. While concubines did not have the same legal status as wives, they were often integrated into the family structure and their children could be considered legitimate heirs.

 

So we see that while the word for concubine has a very narrow meaning, the word for wife is very broad and can mean woman. Therefore it is not difficult to see that while concubine can not be translated as wife (well not a full wife), the word wife (or woman) can be translated as concubine.

The interesting part to me is that the writer of 1 Chronicles knew that they could use the word concubine. This is because we know that the writers of the Bible were inspired by the Holy Spirit (2 Timothy 3:16-17).