Note: There have been several proposals for the structure of the record of the life of Abraham.
This is based on Dorsey
A. 12:1-9 Abram directed to Canaan and promised that his descendant will inherit the land.
Abram 75 years old
B. 12:10-20 Abram in Egypt and wife/sister episode
C. 13:1-18 Abram and Lot separate – Lot towards Sodom, Abram and his descendant(s) promised all the land.
D. 14:1-24 Abram rescues Lot
E. 15:1-21 Abram promised a son, he believes, faith counted for righteousness. Covenant sacrifice made.
F. 16:1-16 Hagar given to Abram, Ishmael born.
Abram 86 years old
G. 17:1-17 God makes a covenant with Abram and changes his name to Abraham. Sarai promises a son and her name changed to Sarah.
F’. 17:18-27 Abraham pleads for Ishmael but Isaac will be the chosen son. Males circumcised.
Abraham 99 years old
E’. 18:1-15 Sarah promised a son.
D’. 18:16-33 Abraham intercedes for the righteous in Sodom (Lot and family)
C’. 19:1-38 Lot delivered from Sodom. Origin of Moab and Ammon.
B’. 20:1-18 Abraham in Philistia and wife/sister episode
A’. 21:1-7 Sarah bares Isaac.
Abraham 100 years old
The following is from Rachel Yudkowsky, “Chaos or chiasm? The structure of Abraham’s life”, Jewish Bible Quarterly, 2007, 35, No. 2, 109-114.
A The descendents of Terah (Gen.11:27)
B. Lekh Leckha [get thee out] (12:1)
C. ‘Unto thy seed will I give this land’ (Gen 12:7). Abraham comes to the land of promise.
D. Sarai is taken in Egypt; Pharaoh sends them away angrily (12:10-20)
E. Sodom: Lot chooses to live in Sodom, is captured by and rescued from the four kings, returns to Sodom (14:1-24)
F. ‘What wilt Thou give me, seeing I go hence childless?’ (15:2)
G. The Covenant Between the Pieces (15:12-21): promise of descendants and land.
H. Birth of Ishmael (16:1-16)
G’. The Covenant of Circumcision (17:1-27): promise of ‘I will be their God’.
F’. Sarah is informed that she will have a child (18:10)
E’. Sodom: Lot rescued from destruction of Sodom and leaves (18:16-19:38)
D’. Sarah is taken in Gerar; Abimelech welcomes Abraham to settle where he wills (20:1-18)
C’. Birth of Isaac, the promised seed ( 21:1-21); treaty with Abimelech, Abraham respected and feared (21:22-34)
B’. “Kakh na . . . ve’lekh lekha” [Take now … and get thee into]. (22:1-19)
A’. Nahor’s descendents (22:20-24)
The Oxford Encyclopedia of Books of the Bible (2011) gives a structure similar to the above and attrributes it to Umberto Cassuto in his Commentary on the Book of Genesis, first written in Hebrew (possibly as early as 1949) and translated into English in 1972. The concentric pattern is
B. First challenge: call to leave family of origin (12:1-3)
C. Wife-sister story (12:10-13:1) – The LORD’s rescue of Abraham in Egypt.
D. Separation from Lot (13:2-18)
E. Covenant of pieces with Abraham (14-15)
F. Hagar-Ishmael story (16:1-14)
E’. Covenant of circumcision with Abraham (17)
D’. Hospitality/progeny episodes; Abraham contrasted with Lot (18-19)
C’. Wife-sister story (20) – the LORD’s rescue of Abraham in Philistia
B’. Final challenge: call to sacrifice family of future (22:1-9)
A’. Epilogue 22:20-24