(1) GOD said to Abram, “Go forth from your native land and from your father’s house to the land that I will show you. (2)I will make of you a great nation, And I will bless you; I will make your name great, And you shall be a blessing.

(22) When Serug had lived 30 years, he begot Nahor. (23) After the birth of Nahor, Serug lived 200 years and begot sons and daughters. (24) When Nahor had lived 29 years, he begot Terah. (25) After the birth of Terah, Nahor lived 119 years and begot sons and daughters. (26) When Terah had lived 70 years, he begot Abram, Nahor, and Haran.

Abram. It is not explicitly stated that he was the firstborn. However, since the biblical text contains no indication to the contrary—... we should understand the text as intending to convey that Abram was the firstborn, and that he was born when his father Terah was seventy years old.

Nahor (נחור).

The fact that he was named after his grandfather, following the practice of papponymy (naming a child after his grandfather), does not imply that he was the firstborn.

On the contrary, perhaps the tradition intended to suggest that it was the second son, rather than the first, who perpetuated the inheritance of the idolatrous family.

The second son, who bore the same name as his grandfather, resembled his grandfather and did not free himself from his spiritual inheritance.

The first son, Abram, however, introduced a momentous and exalted innovation into the life of the family and became an Av-Ram—an exalted father—to a new humanity.

חידש חידוש חשוב ונשגב בחיי המשפחה ... לאנושות חדשה

... he was called Abram as he was the father of Ram, meaning Aram, or Abraham meaning the father of many nations....

“Haran died in the presence of Teraḥ his father in the land of his birth, in Ur of the Chaldeans” (Genesis 11:28).
... Rabbi Ḥiyya grandson of Rav Ada of Yafo: Teraḥ was an idol worshipper [and a seller of idols]. He would say to him: ‘Woe to this man who is sixty years old and seeks to prostrate himself before something that is one day old.’ He would be ashamed and leave.

... He [Teraḥ] said to him: ‘What, are you mocking me? Are they sentient at all?’ He said to him: ‘Do your ears not hear what your mouth is saying?’
He [Teraḥ] took him and handed him over to Nimrod. ...He said to him: ‘Better let us bow down to a person, who can withstand the wind.’ He said to him: ‘You are saying mere words.

“The Lord said to Abram: Go you, from your land, and from your birthplace, and from your father’s house, to the land that I will show you” (Genesis 12:1).
“The Lord said to Abram: Go you, from your land…” – Rabbi Yitzḥak began: “Listen, daughter, see, and incline your ear. Forget your people and your father’s house” (Psalms 45:11). Rabbi Yitzḥak said: This is analogous to one who was passing from place to place, and saw a building with a [candle] burning in it. He said: ‘Is it possible that this building has no one in charge of it?’ The owner of the building looked out at him and said: ‘I am the owner of the building.’ So, because Abraham our patriarch was saying: ‘Is it possible that this world is without someone in charge?’ The Holy One blessed be He looked at him and said to him: ‘I am the owner of the world.’ “The king will desire your beauty, as he is your master” (Psalms 45:12) – to show your beauty in the world. “And bow to him” (Psalms 45:12) – that is, “the Lord said to Abram.”

(2) .....The world continued in this fashion until the pillar of the world - the Patriarch Abraham - was born.

(3) After this mighty man was weaned, he began to explore and think. Though he was a child, he began to think [incessantly] throughout the day and night, wondering: How is it possible for the sphere to continue to revolve without having anyone controlling it? Who is causing it to revolve? Surely, it does not cause itself to revolve.

He had no teacher, nor was there anyone to inform him. Rather, he was mired in Ur Kasdim among the foolish idolaters. His father, mother, and all the people [around him] were idol worshipers, and he would worship with them. [However,] his heart was exploring and [gaining] understanding.

Ultimately, he appreciated the way of truth and understood the path of righteousness through his accurate comprehension. He realized that there was one God who controlled the sphere, that He created everything, and that there is no other God among all the other entities. He knew that the entire world was making a mistake. What caused them to err was their service of the stars and images, which made them lose awareness of the truth.
Abraham was forty years old when he became aware of his Creator. When he recognized and knew Him, he began to formulate replies to the inhabitants of Ur Kasdim and debate with them, telling them that they were not following a proper path.
He broke their idols and began to teach the people that it is fitting to serve only the God of the world. To Him [alone] is it fitting to bow down, sacrifice, and offer libations, so that the people of future [generations] would recognize Him. [Conversely,] it is fitting to destroy and break all the images, lest all the people err concerning them, like those people who thought that there are no other gods besides these [images].
When he overcame them through the strength of his arguments, the king desired to kill him. He was [saved through] a miracle and left for Charan. .......

And in the sixtieth year of the life of Abram, that is, in the fourth week, in the fourth year thereof, Abram arose by night, and burned the house of the idols, and he burned all that was in the house, and no man knew it.

And they arose in the night and sought to save their gods from the midst of the fire.

And Haran hasted to save them, but the fire flamed over him, and he was burnt in the fire, and he died in Ur of the Chaldees before Terah his father, and they buried him in Ur of the Chaldees.

(17) And in the sixth week, in the fifth year thereof, Abram sat up throughout the night on the new moon of the seventh month to observe the stars from the evening to the morning, in order to see what would be the character of the year with regard to the rains,

(18) and he was alone as he sat and observed.
And a word came into his heart and he said: "All the signs of the stars, and the signs of the moon and of the sun are all in the hand of the Lord.

(19) Why do I search (them) out? If He desireth, He causeth it to rain, morning and evening; And if He desireth, He withholdeth it, And all things are in His hand."

(20) And he prayed that night and said "My God, God Most High, Thou alone art my God, And Thee and Thy dominion have I chosen. And Thou hast created all things, And all things that are are the work of Thy hands.

(21)Deliver me from the hands of evil spirits who have sway over the thoughts of men's hearts, And let them not lead me astray from Thee, my God.

(31) And the Lord God said: "Open his mouth and his ears, that he may hear and speak with his mouth, with the language which hath been revealed"; for it had ceased from the mouths of all the children of men from the day of the overthrow (of Babel). And I opened his mouth, and his ears and his lips, and I began to speak with him in Hebrew in the tongue of the creation.

(2) “The Lord said to Abram” – Rabbi Berekhya began: “By the fragrance of your good oils, your name is like poured oil” (Song of Songs 1:3). Rabbi Berekhya said: To what was Abraham our patriarch comparable? To a flask of balsam oil surrounded with a fastened cover, that was placed in a corner and its fragrance did not diffuse. When it was moved, its fragrance diffused. So, the Holy One blessed be He said to Abraham our patriarch: ‘Move yourself from one place to another place, and your name will be exalted in the world.’

(13) A fugitive brought the news to Abram the Hebrew, who was dwelling at the terebinths of Mamre the Amorite, kinsman of Eshkol and Aner, these being Abram’s allies.

(8)... “And told Abram the Hebrew [Ivri]” – Rabbi Yehuda, Rabbi Neḥemya, and the Rabbis,

Rabbi Yehuda says: The entire world was on one side and he was on the other side [ever].

Rabbi Neḥemya said: Because he was among the descendants of Ever.

The Rabbis say: It is because he is from the other side [ever] of the river, and he spoke the Hebrew [Ivri] language.