Now it is time for our verse break down:

Genesis 11:10
These are the generations of Shem: Shem was an hundred years old, and begat Arphaxad two years after the flood:

The Tower of Babel incident of Genesis 11:1–9 is tied to the genealogical table of chapter 10 by the reference to Nimrod, a grandson of Noah’s son Ham, at 10:8–12.

The Babel narrative serves to explain what has preceded and what will follow by connecting the development of distinct nations and cultures to the corresponding distribution of languages.

Following this story, the author resumes the account of the line of Noah’s son Shem. The list in Genesis 11 shows that God’s earlier promise in 3:15—that Eve’s “seed” would bruise the head of the serpent, an allusion to Christ’s victory on the cross—ultimately could not be stopped by the chaos following Babel.

Even though Noah’s descendants are scattered and divided, God’s purpose to redeem His creation through a chosen line is not compromised. This verse begins a genealogy that will directly link Noah's son Shem with Abram, whom God will re-name Abraham (Genesis 17:5).

This sets up the origins of the people of Israel. Unlike the broad, nation-spanning genealogies in chapter 10, this passage tracks a straight line from each man to one of his sons to the next in the line.

This description begins with Shem. Of the three sons of Noah, Shem is the one who is overtly blessed by God (Genesis 9:26). We are told here that Shem fathered Arpachshad two years after the flood when he was 100 years old.

This is the last mention of the flood in Genesis, marking the beginning of a new era. The birth of Arpachshad so quickly after God's command to multiply and fill the earth shows that Shem was living in obedience.

Genesis 11:11
And Shem lived after he begat Arphaxad five hundred years, and begat sons and daughters.

The present genealogy, moreover, being that of Shem, also serves as an adept literary-theological transition to the next thematic “half” of Genesis. The expectation is thus laid that the present genealogy of Shem will likewise be followed by a narrative episode involving the making of a shem (“name”) for a man.

The previous verse began this genealogy linking Shem to Abraham and the Israelites. Shem fathered Arpachshad two years after the flood when Shem was 100 years old. This verse now establishes the pattern for the rest of the genealogy, revealing how long Shem lived after the birth of the next in the line.

Putting the two ages together, Shem lived to be 600 years old, allowing him many years to have other sons and daughters as humanity set about refilling the earth with people. Verse 10 was the last mention of the flood found in Genesis, setting this passage up as a milestone. In the same vein, this genealogy does not focus on phrases such as "and then he died," as did the genealogy of chapter 5.

Genesis 11:12
And Arphaxad lived five and thirty years, and begat Salah:

Observe here, That nothing is left upon record concerning those of this line, but their names and ages; the Holy Ghost seeming to hasten thro' them to the story of Abraham. How little do we know of those that are gone before us in this world, even those that lived in the same places where we live!

Or indeed of those who are our contemporaries, but in distant places. That there was an observable gradual decrease in the years of their lives. Shem reached to 600 years, which yet fell short of the age of the patriarchs before the flood; the three next came short of 500.

The line from Noah to Abraham follows through Shem to Arpachshad and now to Shelah. This is a noteworthy point in Genesis due to the age of Arpachshad when he fathers Shelah: "only" 35 years old. This is a drastic reduction in the age of having children when compared to the pre-flood era (Genesis 5).

Of course, the genealogies listed prior to the flood don't demand those children were the first-born, so those patriarchs might well have had other, earlier children. And yet, it's significant that the ages associated with children are decreasing, as are the lifespans.

Whether as a result of the world being damaged by the flood (Genesis 7:22–24), or by God's direct intervention (Genesis 6:3), humanity's lifespans will taper off very quickly in the generations following Noah. To multiply and fill the earth, people had to start having children at much younger ages.

Genesis 11:13
And Arphaxad lived after he begat Salah four hundred and three years, and begat sons and daughters.

In all, he lived four hundred and thirty eight years; Not mentioned by name: he died, as the above and a Jewish writer says he died in the forty eighth year of Isaac, and who also says, that in his days they began to build the city of Babel.

After fathering Shelah, Arpachshad lived another 403 years and had other children. Adding the numbers together, Arpachshad lived to be 438 years old.

As with other verses, this statement supports a rapid decline in human lifespans after the flood. While ancient figures such as Noah lived nearly a thousand years (Genesis 5), the generations following Abram (Genesis 11:19–26) will be lucky to live beyond a century.

Genesis 11:14
And Salah lived thirty years, and begat Eber:

He had a son born to him five years sooner than his father had. This man was the progenitor of the Hebrews (i.e., Eber’s descendants). The line from Noah to Abraham follows through Shem to Arpachshad to Shelah and now to Eber.

The Eberites and their descendants became a well-known people (Numbers 24:24). As compared to the generations listed prior to the flood (Genesis 5), this verse presents an earlier age of fatherhood, and a shorter lifespan. This is a trend which will continue through the genealogy, as man's life rapidly shortens leading up to the birth of Abram (Genesis 11:19–26).

Genesis 11:15
And Salah lived after he begat Eber four hundred and three years, and begat sons and daughters.

In all, he lived four hundred and thirty three years. After fathering Eber, Shelah lived another 403 years and had other children. Adding the numbers together, Shelah lived to be 433 years old. Patriarchs of the pre-flood world lived close to a thousand years (Genesis 5), and aren't directly said to have had children until having lived more than a century (Genesis 5:3).

As mankind spreads after the flood, these lifespans rapidly decrease. By the time of Abram, a person would be lucky to live beyond a century. And, in stark contrast to the pre-flood world, the prospect of having children near the age of 100 would become incredible (Genesis 17:17).

This might have been due to God's direct influence (Genesis 6:3), or simply as a consequence of living on a harsher, less-ideal planet after the flood.

Genesis 11:16
And Eber lived four and thirty years, and begat Peleg:

Eber lived a total of 464 years. This distinguishes him as the longest living person who was born after the flood. The line from Noah to Abraham follows through Shem to Arpachshad to Shelah to Eber and now to Peleg.

Peleg's name apparently comes from a word that means "to divide." Genesis 10:25 tells us that in Peleg's time the earth was divided, likely referring to the dispersion of the peoples that happened after God confused the languages in Babel (Genesis 11:1–9).

If so, the generations to come after Peleg will live in a drastically divided world. This verse also continues a trend seen in the genealogy of Genesis 11: decreasing lifespans. Children are mentioned at younger ages, and years of life are much shorter.

This change takes a particularly dramatic jump in the time between Eber and Peleg—those living after the Tower of Babel seem to have lifespans around half of what they were prior to that incident (Genesis 11:17–19).

Genesis 11:17
And Eber lived after he begat Peleg four hundred and thirty years, and begat sons and daughters.

All the years of his life were four hundred and sixty four: One of which is elsewhere mentioned, whose name is Joktan, Genesis 10:25 according to the above Jewish writer, he died in the seventy ninth year of Jacob.

After fathering Peleg, Eber lived another 430 years and had other children. Adding the numbers together, Eber lived to be 474 years old.

Peleg is noteworthy for his connection to the incident at the Tower of Babel (Genesis 11:1–9).

His name is associated with earth being "divided" (Genesis 10:25).

This link also helps to make sense of the sudden drop in lifespans. While post-flood lives are already shortening, compared to the patriarchs of chapter 5, Peleg and those who follow him will live half as long as his father Eber. Within a few more generations, man's days are cut down again by half (Genesis 11:19–24).

Genesis 11:18
And Peleg lived thirty years, and begat Reu:

He was 30 years old when he fathered Reu. The line from Noah to Abraham follows through Shem to Arpachshad to Shelah to Eber to Peleg and now to Reu. The name Reu appears only here in the Old Testament, though it may be a variation on other names.

This verse is otherwise interesting for mentioning Peleg, a name associated with the division of humanity at the Tower of Babel (Genesis 10:25; Genesis 11:1–9).

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