Parallel
Genesis 21:4
Swete's Septuagint · Berean Standard Bible
περιέτεμεν δὲ Ἀβραὰμ τὸν Ἰσαὰκ τῆ ὀγδόῃ ἡμέρᾳ, καθὰ ἐνετείλατο αὐτῷ ὁ θεός.
When his son Isaac was eight days old, Abraham circumcised him, as God had commanded him.