12:4 Possibly Abram viewed Lot as his heir (cf. 11:27-32; 12:4-5; 13:1-2).
"Since Mesopotamian law-codes allowed for the adoption of an heir in the case of childlessness, this becomes an attractive hypothesis with respect to Lot."427
Abram lived 75 years with his father, then 25 years without his father or his son, and then 75 more years with his son, Isaac.
12:5-6 Abram's first settlement was in Shechem.
". . . towns on the main caravan route southwestward from the Euphrates which figure significantly in the Abram stories, are Shechem, Bethel, Hebron, and Gerar."428
Shechem became sacred to the Israelites because here God revealed Himself to Abram for the first time in the Promised Land. This was God's second major revelation to Abram. At Shechem Jacob later bought land, set up his home, and buried his idols in rededication to Yahweh after returning from his sojourn in Paddan-aram (33:18-20; 35:4). Here, too, the Israelites assembled twice when they had taken possession of Canaan under Joshua's leadership to commemorate God's faithfulness in giving them the land He had promised their forefathers (Josh. 8, 24). Shechem was near the geographic center of Canaan (cf. Josh. 20:7). It lay in the heart of the land God now promised Abram.
The reference to the Canaanites' presence in the land prepares the way for incidents of conflict with these native inhabitants that followed in Israel's history (cf. 10:15-19). It also notes a barrier to the fulfillment of God's promise to give Abram and his heirs the land (v. 7). Abram could not take possession of the Promised Land immediately because the Canaanites occupied it.
12:7 In response to God's promise to give Abram the land where he stood the patriarch built an altar and worshipped Yahweh. This was Abram's characteristic response to God's grace. Abram's altars were more permanent structures than his tents. He continued living as a pilgrim and stranger in a land that he did not yet possess (Heb. 11:9-10).
12:8 Abram proceeded south and encamped between Bethel and Ai (probably et Tell429) just north of Salem (Jerusalem). Again he built an altar to worship Yahweh and called on His name in worship.
12:9 He next continued south toward the Negev, perhaps because of a shortage of food for his grazing animals (v. 10).
The nation of Israel in Moses' day shared the same call that God had extended to Abram. She was to leave her place of residence, Egypt, and go to a Promised Land to worship and serve God there with the promise of blessing. This required faith. We have a similar calling. Believers who walk by faith will forsake much to become part of God's program to bless the world.