12 So Abram left. This is the report of Abram’s obedience to God’s command (see v. 1).
13 Heb “just as the Lord said to him.”
14 The disjunctive clause (note the pattern conjunction + subject + implied “to be” verb) is parenthetical, telling the age of Abram when he left Haran.
15 Heb “was the son of five years and seventy year[s].” Terah was 70 years old when he became the father of Abram, Nahor, and Haran (Gen 11:26). Terah was 205 when he died in Haran (11:32). Abram left Haran at the age of 75 after his father died. Abram was born when Terah was 130. Abram was not the firstborn—he is placed first in the list of three because of his importance. The same is true of the list in Gen 10:1 (Shem, Ham and Japheth). Ham was the youngest son (9:24). Japheth was the older brother of Shem (10:21), so the birth order of Noah’s sons was Japheth, Shem, and Ham.

In other versions

So Abram went, as the Lord had told him, and Lot went with him. Abram was seventy-five years old when he departed from Haran.

So Abram went, as the Lord had told him; and Lot went with him. Abram was seventy-five years old when he set out from Harran.

So Abram went, as the Lord had told him, and Lot went with him. Abram was seventy-five years old when he left Haran.

So Abram departed as the Lord had instructed, and Lot went with him. Abram was seventy-five years old when he left Haran.

And Abram went out as Yahweh had told him, and Lot went with him. Now Abram was seventy-five years old when he went out from Haran.

So Abram departed, as the Lord had spoken unto him; and Lot went with him: and Abram was seventy and five years old when he departed out of Haran.

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