And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also:
Ver. 11. A seal of the righteousness] Circumcision is called a sign and a seal by a doctor of the Jews more ancient than their Talmud Zohar, Gen 17:9-14
That righteousness might be imputed] How foolish is that inference of Thammerus, that because the word here used to signify imputed comes of a word that signifies reason, therefore the righteousness of faith must be such as a man may understand and comprehend by reason (λογισθηναι, λογος).