Remarkable is that God is still walking among men in these chapters. They have conversations with him and no one really sees it as miraculous. It’s worth remembering that Abram, now called Abraham, is being advised by his family god which his father Terah brought from Babylon when they went east to establish a new colony.
The Patriarchal Age, from Genesis 12 through 50, cover the lives of Abraham, Isaac, and Jacob. It’s preceded by the Primeval Age, Genesis 1 through 11, and followed by Exodus.
Per modern scholars and archeologists, Abram ben Terah was born in Ur around 2150 BCE and died in Hebron, Canaan, present-day West Bank, around 1975 BCE.
God declares that he is the one, true god (Genesis 17:1). This is the shift where Yahweh transitions from the household God and protector of Abraham’s father, Terah to being the only God.
God promises to Abraham is that he will be fruitful and will be the father of many nations (Genesis 17:2-7) and that God will be the God of all of his descendants.
God bequeaths Abraham and his descendants the land of Canaan for eternity (Genesis 17:8-9).
In exchange, Abraham, his household and his descendants will perform circumcision as a token of this covenant (Genesis 17:10-13).
Any who are not circumcised will be will be cut off from God’s people as they’ve rejected his covenant (Genesis 17:14).
Sarai, Abraham’s wife, shall be called Sarah. She will be blessed and will bare a son. His descendants will be kings to all the people whom God has chosen (Genesis 17:15-16).
Abraham protests, as he is 99 and Sarah is 90 (Genesis 17:17-18).
God reassures Abraham that Sarah will bare a son called Isaac, who will have the covenant as will his descendants (Genesis 17-19).
As for Ishmael, Abraham’s son with Hagar, he will be blessed and will beget 12 princes and many nations (Genesis 17:19), but only Abraham’s and Sarah’s son Isaac will hold the covenant with God (Genesis 17:20).
God leaves and Abraham circumcises Ishmael, all the other men of his household, including his slaves (Genesis 17:21-27).