Was Boaz the Son of Rahab?

Almost every year when teaching through Old Testament survey class, I get asked whether Boaz was the son of Rahab. According to the genealogy of Matthew 1:5, Salmon was the father of Boaz by Rahab. So that seems to settle the issue then. Many people assume that Boaz was Rahab’s son, and perhaps Rahab herself would have told stories to Boaz about God’s gracious intervention in her life. Rahab being the mother of Boaz certainly preaches well! However, there are some complications.

Boaz Probably Lived 200+ Years After Rahab

We have a bit of a conundrum, because Ruth 4:21–22 gives us David’s likely relationship with Boaz. We can trace David’s genealogy as follows:

• Salmon fathered Boaz
• Boaz fathered Obed
• Obed fathered Jesse
• Jesse fathered David

We know David becomes king over Judah around 1010 BC. So, if we trace the Ruth genealogy, we see that the story of Boaz probably took place shortly before 1100 BC. We can calculate that by running the following numbers of a likely age when the individuals would certainly have children, plus how old David was when he became king.

Obed (25 years) + Jesse (25 years) + David (40 years) = 90 years

We also know that the story of Rahab takes place in 1406 BC (40 years after the Exodus, 1446 BC). So, if we run the numbers, Rahab (1406 BC) and Boaz (1100 BC) are too far apart to be a mother and son.

Even if we add another 50 years to Boaz’s genealogy and 50 years to Rahab’s story (to give her time to have children), that still means that Rahab and Boaz are separated by about 200 years. In other words, it is simply not possible for Boaz to be the son of Rahab if Ruth’s genealogy is complete.

Could Matthew be Referring to a Different Rahab?

This is a valid question. However, it is unlikely that Matthew is talking about a different woman named Rahab. It is already rare that Matthew would mention women in the genealogy. Although Matthew mentions four (Tamar, Rahab, Ruth, and the wife of Uriah), it was not common in genealogies to list women. Importantly, each of the other women figured prominently in Israel’s history, so it is unlikely that Matthew would mention a different woman (Rahab) that did not have significant prominence in the biblical narratives.

Genealogies Regularly Skip Generations

A final factor to consider in this issue is that genealogies regularly skip generations. This is kind of abnormal for us, as we like to know every single detail of genealogical descent. But, it is a well-known fact in biblical studies that genealogies will often skip generations.

One example of this from the Old Testament is Exodus 6, in the genealogy of Moses and Aaron. Moses and Aaron are brothers and are sons of Amram (Exod 6:20). Amram is said to have been a son of Kohath (Exod 6:18), who is said to be a son of Levi (Exod 6:16). So, piecing together the genealogy of Exodus 6, we see the following relationship:

• Levi (son of Jacob) fathered Kohath
• Kohath fathered Amram
• Amram fathered Moses and Aaron

We know that Moses was 80 years old during the Exodus (1446 BC), and he had had children before that time. So, if we wildly assume 80 years per generation (a crazy and much-too-high assumption), we would produce the following time span:

Kohath (80 years) + Amram (80 years) + Moses (80 years) = 240 years

Even if we add another 60 years just to make sure we are being completely ridiculous, we still only have 300 years of generations discussed in Moses’s genealogy.

Scholars have established that Jacob and his sons entered Egypt in 1876 BC.

So, if Jacob and his sons (including Levi), enter Egypt around 1876 BC then we would expect the Exodus to take place 240 to 300 years later (ca. 1576 BC?). But we can firmly date the Exodus to 1446 BC (cf. 1 Kings 6:1).

So, although it was 430 years between Levi and Moses’s generation. The genealogy of Exodus 6 only gives a maximum of 300 years of data (and that is a much too high estimate). Clearly, Exodus 6 is dropping certain generations for the sake of conciseness.

Does Matthew Skip Generations?

Given the above data, it should come as no surprise that Matthew skips generations in the genealogy in Matthew 1:2–16. He likely abbreviates the genealogy in vv. 3–4, because he only gives four generations from Perez to Amminadab (a time span of 400 years). Matthew also unquestionably alters the genealogy in verse 8 and 9 by dropping kings Ahaziah, Joash, and Amaziah from the list. So, Matthew abbreviates the genealogy in at least two places.

Intriguingly, Matthew structures his genealogy into 3 groups of 14 each. Some have surmised this is an example of gematria, where a numerical value stands for a person. It just so happens that David’s Hebrew numerical value is 14. Some have hypothesized that Matthew was constructing the genealogy to emphasize David’s relationship to the Messiah. Regardless, the point is, Matthew is not giving full genealogies, but just presenting selected names.

Is Boaz the Son of Rahab?

I will conclude by noting that Hebrew familial terms have tremendous flexibility. It is completely within the bounds of culture and custom to call someone a son, who was a farther descendant. Classical Hebrew used the term son to communicate many relationships on the family spectrum. It was appropriate in Hebrew culture to refer to a grandson or great-grandson as a “son.”  

Therefore, it is unlikely that Boaz is the son of Rahab, at least how we think of “son.” It is far more likely that a few names have dropped out of the genealogy, and that Boaz was a great-grandson or perhaps a great-great-grandson of Rahab. Although, we should also note that it is possible that Boaz could be closely related to Rahab, and perhaps the names that have dropped out in the genealogy are between Boaz and David, not between Rahab and Boaz. Still, all things considered, I believe it is more likely that Matthew has abbreviated the genealogy between Rahab and Boaz, and although he was related to Rahab, he was probably not her son.

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