Genesis 21:3-4

21:3 Abraham named his son – whom Sarah bore to him – Isaac. 21:4 When his son Isaac was eight days old, Abraham circumcised him just as God had commanded him to do.

tn Heb “the one born to him, whom Sarah bore to him, Isaac.” The two modifying clauses, the first introduced with an article and the second with the relative pronoun, are placed in the middle of the sentence, before the name Isaac is stated. They are meant to underscore that this was indeed an actual birth to Abraham and Sarah in fulfillment of the promise.

tn Heb “Isaac his son, the son of eight days.” The name “Isaac” is repeated in the translation for clarity.

sn Just as God had commanded him to do. With the birth of the promised child, Abraham obeyed the Lord by both naming (Gen 17:19) and circumcising Isaac (17:12).