What does Genesis 12:8 mean?
After the Lord appeared to Abram at Shechem and promised to give the land to Abram's descendants, Abram and his large company moved on to the region between Bethel and Ai. We're told Abram "pitched his tent" there. This phrasing seems to imply that Abram and his people settled there for some time.Also while east of Bethel, Abram builds an altar to the Lord and calls on His name there. The implication here may be that Abram began to participate in regular, formal worship of Yahweh in this place. The terminology is similar to that of Genesis chapter 4, where people are said to begin to "call upon the name of the Lord" after the banishment of Cain, and the birth of Seth (Genesis 4:26). As with the altar at Shechem, no mention is made of animal sacrifices.
Genesis 13:4 records that Abram later returned to this altar and called on the Lord's name again. This strongly suggests this altar was a lasting structure and not merely a temporary arrangement.