Bereshit 15 – One Prophecy or Two?


Internal Inconsistencies

Bereshit 15 is comprised of two sections, verses 1-6, in which Hashem promises Avraham plentiful seed, and verses 7-21, known as the Covenant of the Pieces, in which He tells Avraham that his progeny will inherit the Land of Israel.  At first glance, the two parts of the chapter seem to constitute two halves of an integrated blessing of seed and land. Yet, on a closer look, several verses and seeming inconsistencies between the two sections challenge that assumption:

Relationship to Earlier Promises

Although this is not the first time that Avraham receives blessings of progeny and land, this episode stands out from earlier ones both in the manner of Hashem's blessing and in Avraham's reaction to it:

400 or 430 years?

During the covenant, Hashem shares with Avraham that his children will be exiled for 400 years:
יָדֹעַ תֵּדַע כִּי גֵר יִהְיֶה זַרְעֲךָ בְּאֶרֶץ לֹא לָהֶם וַעֲבָדוּם וְעִנּוּ אֹתָם אַרְבַּע מֵאוֹת שָׁנָה.

However, in Shemot 12:40 the Torah records that the Israelites were in Egypt for 430 years:

וּמוֹשַׁב בְּנֵי יִשְׂרָאֵל אֲשֶׁר יָשְׁבוּ בְּמִצְרָיִם שְׁלֹשִׁים שָׁנָה וְאַרְבַּע מֵאוֹת שָׁנָה.

How can these two verses be reconciled?

The various difficulties raised above prompt commentators to question both the relationship between the various sections of the chapter and the chronology of the events.