Throughout the book of Genesis, YHWH has been telling Abraham that his descendants will one day possess the land of Canaan, which usually meets with skepticism from Abraham. His sometimes sister, sometimes wife, Sarah, is barren and said to be well beyond the age when women could produce children. YHWH has gone so far as to change Abraham and Sarah’s names, and introduce the ritual of circumcision to Abraham to prove he means business. In Genesis 21, YHWH walks the walk instead of just talking the talk, and Sarah conceives and gives birth to a son, who they name Isaac. Abraham is said to be one hundred years old at the time, so we must assume Sarah is close to that age, since she’s been with him all along.
Of course, nowadays, we know one hundred year old women are no longer capable of giving birth, and most would have no intentions to do so if they could. Assuming she was a legend and not a myth, Sarah was probably in her early to mid-50s, a considerably advanced age for a woman of that time, and would have been perceived as too old to give birth, though it is still a possibility at that age. Genesis later records that Sarah dies before Abraham, and given how difficult childbirth is for a woman of any age, the rigors of a nomadic lifestyle, in addition to her advanced age would have made the process much more hazardous. Why it was deemed necessary to wait so long is one of the enduring mysteries of Genesis. In all probably, the story that’s recorded was influenced by the legend of Abraham fathering a child at an advanced age, which suggests Ishmael and Isaac may not have been his only offspring, since prominent men were allowed to have as many wives and concubines as they could support, and Abraham is constantly said to be one of the most prominent. It’s unlikely he was really one hundred, since the life expectancy wasn’t more than forty to fifty, and his many swashbuckling adventures, such as saving Lot, would have meant that he’d have needed to be exceptionally spry for his age, but he could have been in his sixties or seventies, which might have seemed like a hundred to people not accustomed to living past forty.
Speaking of Ishmael, the birth of Isaac creates problems for him and his mother Hagar. Genesis tells us Sarah catches Ishmael “mocking” during the celebration of Isaac’s circumcision. She orders Abraham to send Hagar and Ishmael away, and Abraham isn’t happy about it, until he receives word from YHWH that Ishmael will also be the progenitor of a significant tribe, just for being Abraham’s son. Abraham gives them some provisions and water and they wander out into the desert. When the water runs out, Hagar puts Ishmael under a bush and moves some distance away from him, so she doesn’t have to watch him die. YHWH hears Ishmael crying and sends an angel to tell Hagar everything will be okay, then leads her to a well. Later, Hagar finds him a bride from among the Egyptians. From here on, we’re done with Ishmael until Abraham dies.
Abraham’s old pal Abimelek makes another appearance. Readers will recall that when these two met in the previous chapter, Abimelek tried to take Sarah as his wife, believing her to be Abraham’s sister and much younger than she actually is, which prompted a vision from YHWH to tell him it wasn’t such a good idea. Now Abraham approaches Abimelek about a well which is being disputed by some of his people. Abimelek seems stunned to hear about the situation with the well in question and he and Abraham agree to enter into a treaty over it, known as the Treaty of Beersheba. Finished bestowing Abraham with another sweet deal over water rights, Abimelek heads out with his army commander back to his kingdom. Abraham plants a tamarisk tree, and calls on the Eternal God, something we’ve not heard YHWH called in Genesis before, which concludes the episode.
There’s not a lot of obvious embellishment with the story, though some details raise some questions. As previously stated, it’s not clear why it was necessary to constantly remind Abraham that descendants of his, several hundred years in the future, will inherit Canaan. Obviously, readers with several thousand years of hindsight will understand the significance of these promises, but it’s not clear what a nomadic herdsman is supposed to do with the information. Abraham seems to have spent most of his time guiding his sizable flocks and herds throughout the region from Babylon to Egypt, telling people his wife is his sister and using the fallout from it to craft deals for more livestock, water, and grazing lands. He must have been a towering figure in the folklore to occupy such an important place in the history of the Children of Israel, though the stories in Genesis don’t always demonstrate why that is. He has certainly seemed very resourceful and shrewd, and his relationship to YHWH is unparalleled among most in the Bible, with the possible exception of Joseph or David.