Exodus (Shemot in Hebrew) segues from Genesis (Bereshit), for good reason.
Here are four rationales that explain what takes us from the Torah’s first to second book.
1) Bereshit dealt with individuals of great personal stature. To name some of the moral giants, we
list: Adam, Noach, Shem, Eiver, Avraham, Yitzchak, Yaakov and his sons. There were other
outstanding personalities, as well. After the narratives of these men of note were completed,
Sefer Shemot commenced. Emphasis changes track from holy individuals to the holy Hebrew
nation. Given the private/collective parameter, really, the Torah’s first book could aptly be
called “The Book of Individuals”; the second book “The Book of the Nation.”
2) A second rationale requires a deeper look, addressing the bedrock question: Why did God
transmit the Torah? Answer: He desired to refine the Chosen People, His flock, through
education and mitzvot. Scripture and its teachings uplift and enlighten body and soul. However,
when the divine Torah sought to chronicle this unique and holy people, it first provided their
backstory. In the beginning was their family tree. Indeed, worthy stock, blessed by the Maker.
The Jews hail from a dedicated and close-knit religious-minded community. Remarkable men
honed their descendants for nobility.
Of course, all mankind descends from Adam and the Torah is saying more than who begot whom.
Bereshit, metaphorically speaking, is a story about separating the wheat from the chaff, fruit from its
peel. The men of renown are likened to what is ethically precious, morally craven descendants of Adam
to byproduct discarded. Adam’s third son, Shet, was a cultivated, sweet fruit, a towering individual, a
striking figure etched in God’s image.
But not all of Shet’s descendants stayed the course. Many fell into the fruit peel category. Jews were of
a different ilk. In time, Noach arrived, “a pure, tzaddik” to quote Bereshit. 6 The Torah relates that Noach
found favor in the Creator’s eyes.  Yet, again, not all of the ancient mariner’s sons followed God.
Specifically, Cham and Yafet didn’t, and are thus relegated to chaff, summarily dismissed. Shem, in
contrast, held the flame, as did his great grandson Eiver, as did his great grandson Avraham. Avraham
had it all, a delectable fruit, an indefatigable doer of good and a constant truth seeker. Of his offspring, 
Yitzchak shined most brightly, all others marginalized. From Yitzchak came Yaakov. While Esav was
detested, Yaakov rose in stature, a veritable Torah-value repository. Yaakov’s twelve sons clung to their
father’s ways, all glimmering wheat stalks. Together, father and sons forged the holy nation, each one
steadfast to Torah principles.
And the Maker rewarded them, showering them with divine favor or providence. 8 In sum, the role of
Bereshit provides an important contribution to understanding the roots of the Jewish People, their
ancestry. Shemot recalls the greatness of the nation, and its religiosity.
3) The Torah’s first book conveys the mighty deeds of the patriarchs, their holiness and divine
communiqués. Hence, we read about the lives of Adam, Noach and his three sons, and all of their
successive generations. This is by way of background until we reach Avraham. Avraham’s wholeness
surpassed that of his predecessors. This observation is borne out by the fact that the Torah writes three
parshiyot about his lifetime. For Yitzchak, the Torah dedicated one entire parashah. And in testimony to
Yaakov’s and his son’s prominence, we count three pashiyot. Yosef and his brothers comprise Bereshit’s
final three parshiyot. All tallied, the Torah’s first book consists of twelve parshiyot, all training a light on
the patriarchs’ positive traits and contributions.
Moshe’s attainments, by contrast, soared above the rest, equal to the sub-total of them. And in the field
of prophecy, he far outdistanced them. That explains why Shemot’s twelve parshiyot pertain to the seer.
In that regard, Bereshit’s scorecard, if you will, hints at the predominance of Moshe. An entire book
belongs to the prophet, one equal to the Torah’s first book. Bereshit’s subjects are the patriarchs (and
their forerunners); Shemot’s subject matter is Moshe.
4) Finally, the divine Torah writes the epic story of how God took in His flock, the House of Yaakov. But
first, readers needed to learn of Avraham’s, the first patriarch’s, sterling character. Still, Avraham had
not been born into a vacuum. His illustrious forebears, to name some, were Adam, Noach, Shem, and
Eiver. Avraham, morally and ethically evolved from them.
Within Avraham’s story we read about a divine covenant, known as the brit bein ha’betarim. It foretells,
“Your seed shall be strangers in a strange land.”  The covenant or brit also spoke of prodigious offspring,
and a Holy Land which they could call home. Finally, in that brit, Avraham learned that God would
extend His providence over the patriarch’s descendants, and His close attachment or devekut to them.
The balance of Bereshit reveals how covenantal promises play out. Thus, for example, we read about
Yaakov’s and Esav’s intrauterine posturing.  Later, there was a noxious sibling rivalry between Yosef and
his brothers. Finally, a fierce famine forced Yaakov’s and his family’s descent into Egypt. Sowed were the
seeds of national exile and redemption.Bereshit, then, lays the prefatory foundation upon which Shemot may be built. Put differently, theTorah’s first book introduces the ills and travails that precipitated a multi-century exile, one with
disastrous consequences for the fledgling nation.
 It also opened a window. At the end of the calamitous sojourn in Egypt’s hell, salvation came – the
exodus. That was only the half of it. On Sinai, the Hebrews acquired the requisite skillset to reach
religious heights. Divine providence and the Shechinah nestled into the people’s desert camp, housed in
the Tabernacle or Mishkan. To sum up, Bereshit brings the root causes (rivalry and famine); whereas,
Shemot discusses the consequence (read: the second book elaborates on exile and exodus).

We now better appreciate the divine wisdom that sequenced the order of Bereshit’s and Shemot’s parshiyot. As for the author, all had been transcribed by Moshe, at the word of God. Moreover, the prophet received commentary on all that the Creator communicated to him. After we have laid out these four introductory rationales, we proceed to Shemot’s commentary, with God’s help.