What is the meaning of Romans 4:9-10?

9 Cometh this blessedness then upon the circumcision only, or upon the uncircumcision also? for we say that faith was reckoned to Abraham for righteousness. 10 How was it then reckoned? when he was in circumcision, or in uncircumcision? Not in circumcision, but in uncircumcision. (Romans 4:9-10 KJV)

William Burkitt’s Commentary

Here Apostle Paul moves the question, namely, Whether the aforementioned blessedness of pardon of sin, and justification by faith, belongs to the circumcised Jews only, or to the uncircumcised Gentiles also? which question carries with it the force of a strong affirmation, that seeing faith was imputed to Abraham for righteousness many years before he was circumcised; therefore the uncircumcised Gentiles, as well as the circumcised Jews shall by faith be made partakers of the same blessedness, unto which Abraham was entitled before he was circumcised.

Learn hence, That God has appointed one and the same way and method for the justification and salvation of all persons, circumcised and uncircumcised, Jew and Gentile, honourable and ignoble; namely, justification by faith in the blood of his Son, without which no church privileges or spiritual prerogatives whatsoever will entitle them to real blessedness.  Cometh this blessedness on the circumcision only, or upon the uncircumcision also? Abraham believed unto righteousness before he was circumcised; therefore, the Gentiles by faith shall be accounted righteous, though they never were circumcised.