After the fall spread across the nations, God called one man to carry one promise: descendants, land, and blessing for all families of the earth through him. Abraham believed God, and it counted as righteousness, which is why everyone who believes today is called his child.
Not a summary of these passages: the passages themselves. Read them, then come back to the study below.
The study
What the Scripture says
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God's answer to Babel was a person, not a program
After humanity's pride scattered the nations, God did not launch a reform movement. He told one seventy-five-year-old, childless man to leave everything behind for 'the land that I will show you.' Salvation history funnels through one family so that the blessing can later fan out to every family on earth.
Now Yahweh said to Abram, “Get out of your country, and from your relatives, and from your father’s house, to the land that I will show you.Now the Lord had said unto Abram, Get thee out of thy country, and from thy kindred, and from thy father’s house, unto a land that I will shew thee:
He said, “Brothers and fathers, listen. The God of glory appeared to our father Abraham, when he was in Mesopotamia, before he lived in Haran, and said to him, ‘Get out of your land, and from your relatives, and come into a land which I will show you.’And he said, Men, brethren, and fathers, hearken; The God of glory appeared unto our father Abraham, when he was in Mesopotamia, before he dwelt in Charran, And said unto him, Get thee out of thy country, and from thy kindred, and come into the land which I shall shew thee.
'All of the families of the earth will be blessed in you': Abraham was chosen not for privilege alone but for mission. Paul reads this precisely: God announced the gospel in advance to Abraham when He promised that the nations would be blessed through him. The promise always aimed past Israel at the world.
I will bless those who bless you, and I will curse him who curses you. All of the families of the earth will be blessed in you.”And I will bless them that bless thee, and curse him that curseth thee: and in thee shall all families of the earth be blessed.
The Scripture, foreseeing that God would justify the Gentiles by faith, preached the Good News beforehand to Abraham, saying, “In you all the nations will be blessed.”And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed.
When Abraham worried that his servant would inherit everything, God pointed him at the stars and repeated the promise, and 'He believed in Yahweh; and he reckoned it to him for righteousness.' Before any ritual, any law, any sign, Abraham was right with God by trusting Him. That is why faith, not descent or performance, marks his true children.
He believed in Yahweh; and he reckoned it to him for righteousness.And he believed in the Lord; and he counted it to him for righteousness.
For what does the Scripture say? “Abraham believed God, and it was accounted to him for righteousness.”For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness.
Know therefore that those who are of faith, the same are children of Abraham.Know ye therefore that they which are of faith, the same are the children of Abraham.
In the strange ceremony of Genesis 15, God had the animals cut in pieces, and only the smoking firepot and flaming torch passed between them while Abraham slept. In that culture both parties walked the path; here only God did. The promise is guaranteed by His character alone, which is why Abraham's failures and ours cannot break it.
It came to pass that, when the sun went down, and it was dark, behold, a smoking furnace, and a flaming torch passed between these pieces.And it came to pass, that, when the sun went down, and it was dark, behold a smoking furnace, and a burning lamp that passed between those pieces.
Now Yahweh said to Abram, “Get out of your country, and from your relatives, and from your father’s house, to the land that I will show you. I will make of you a great nation. I will bless you and make your name great. You will be a blessing. I will bless those who bless you, and I will curse him who curses you. All of the families of the earth will be blessed in you.”Now the Lord had said unto Abram, Get thee out of thy country, and from thy kindred, and from thy father’s house, unto a land that I will shew thee: And I will make of thee a great nation, and I will bless thee, and make thy name great; and thou shalt be a blessing: And I will bless them that bless thee, and curse him that curseth thee: and in thee shall all families of the earth be blessed.
The Scripture, foreseeing that God would justify the Gentiles by faith, preached the Good News beforehand to Abraham, saying, “In you all the nations will be blessed.”And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed.