In what context was it credited? Was it after his circumcision, or before? It was not after, but before.
Abraham received justification by faith fourteen or twenty-five years before circumcision, silencing the fears of the uncircumcised Gentiles and humbling the pride of the Jews who boasted in their circumcision as if it held a monopoly on blessing. Circumcision came only afterward as a seal and confirmation of righteousness already imputed.
AI summary
Commenting on Romans 4:9-16
And he received the sign of circumcision,.... Or "the sign circumcision", as the Syriac version reads it, and so the Alexandrian copy, and two of Stephens's; that is, Abraham received at the hands of God, the commandment of circumcision, which was a "sign" or token of the covenant; not of grace, but of that peculiar covenant God made with Abraham and his natural seed, concerning...
Verse 10. How. In what circumstances, or time. When he was in circumcision, etc. Before or after he was circumcised? This was the very point of the inquiry. For if he was justified by faith after he was circumcised, the Jew might pretend that it was in virtue of his circumcision; that even his faith was acceptable, because he was circumcised.