See Genesis 12.1-2. From this point until verse 20, the writer is mainly concerned with Abraham, but this theme is interrupted in verses 13-16 by a more general statement, and perhaps in verse 11 by a reference to Sarah (see comments). It is impractical, as well as a distortion of the author’s careful method of writing, to rearrange the verses in order to bring everything on Abraham together.
Made Abraham obey: a different word for obey from that used in verse 7 is used here, but there is no difference in meaning. It may be necessary to state who obeys whom; for example, “Because Abraham trusted God, Abraham obeyed him.”
When God called him makes explicit what is implied in the literal passive expression “when he was called.” God called him means “when God told him to leave Haran for an unknown destination,” not “when God gave him the name Abraham” (see Gen 17.5), as in some manuscripts.
In some languages it may be necessary or more natural to state from where Abraham to go out to. It may be impossible to employ a literal rendering of to go out to, since this would suggest leaving an enclosure such as a room or house. An equivalent may be “to go away to,” “to leave in order to go to,” or simply “to go to.”
A country is quite general in meaning; it is literally “a place” (King James Version). Which God had promised to give him makes God explicit and shows that “inheritance” (Revised Standard Version), as in the previous verse, has its more general meaning of “a gift,” in this case from God.
He left his own country is literally “he went out,” which uses the same verb rendered to go out to.
It may be necessary to reverse the order of He left his own country and without knowing where he was going; for example, “Even though he did not know where he was going, he left his own country” or “He did not know where he was going, but he left his own country.”
Quoted with permission from Ellingworth, Paul and Nida, Eugene A. A Handbook on The Letter of the Hebrews. (UBS Handbook Series). New York: UBS, 1983. For this and other handbooks for translators see here .