Everything that happens to this guy in some way anticipates what it meant to be an Israelite and what it now means to be Jewish. Let's take a look at a few of the major events in his life that are archetypal or foundational for the nation of Israel as a whole:
Land: God commands Abraham to leave his home and go to the land of Canaan or modern-day Israel-Palestine, then God promises that all of this will one day belong to his descendants (12:1-9; 13:14-15; 15:7, 18-21; 17:8). Yep. We're still arguing over that today.
Covenant: God makes a "covenant" with Abraham, which is a fancy way of saying that the two of them cut a deal. God promises that Abraham's descendants will be as numerous as the stars, will inherit the land of Canaan, and will become a mighty nation. In return, Abraham and his descendants are supposed to walk with God and be circumcised (15:1-21; 17:1-16). The takeaway here is that Abraham and (later) the nation of Israel claim to have a pretty special relationship with this deity.
Circumcision: All male children are supposed to be circumcised when they're eight days old, and Abraham is the first to give the snip to all of the ding-dongs in his household. Some later ancient writers even make fun of this practice—don't cut too much off, they warn. And as you probably know, the practice still persists to this day.
Exodus: The years of slavery in Egypt and Israel's subsequent deliverance by God is a story familiar to anyone who's read the first chapters of the biblical book of Exodus or seen Cecil B. DeMille's well-known flick. Well, Abraham gets a sneak peak at all this, even though it won't happen for many generations after his death (15:13-16).
As important as he is, Abraham still has to struggle with things that all of us mortals can relate to. Above all, God makes huge promises to Abraham, but they don't come about right away or very easily—if at all:
So Abraham receives some big promises, but he has to survive in the real world without God's help. How does he do it? Well, he gets pretty good at wheeling and dealing. He doesn't hesitate to tell fibs to save his life (12:10-20; 20:1-17). He enters into difficult negotiations over property with very powerful figures (14:21-24; 21:22-34; 23:1-20). And he fights and wins wars and makes strategic alliances (14:13-20).
Turns out to work pretty well for him, too. Abraham becomes one rich dude. Somehow he works his little lie about Sarah being his sister to such advantage that Pharaoh and Abimelech give him valuable stuff and even money (12:16; 20:16). He's in charge of warriors who fight for him (14:14), has plenty of servants to do his bidding (12:16; 15:2; 16:1; 22:3, 19), and is wealthy enough at the end of his life to woo a wife for his son by giving her money, nose rings, and jewelry (24:22, 30, 53). Not too shabby for an underdog.
Thanks to the Paul's letters to the Romans and Galatians (check out Romans 4:3 and Galatians 3:6), Abraham is probably most famous for his "faith." The one verse everyone knows from Abraham's story is Genesis 15:6, "And he believed the Lord; and the Lord reckoned it to him as righteousness."
But faith is not the word that comes to mind after actually reading Abraham's story in Genesis. After all, this guy's got the pluck to sass God, and he really is kind of wily when it comes to his relation with the deity. Let's take a look:
Sure, Abraham believes in God, as 15:6 reports, but he ain't no pushover.