A.T. Robertson Commentary Romans 2:26

"If therefore the uncircumcision keep the ordinances of the law, shall not his uncircumcision be reckoned for circumcision?" — Romans 2:26 (ASV)

Keep (φυλασση). Present subjunctive with εαν, condition of third class, mere supposition like that in verse 25, "keep on keeping" perfectly, Paul means.

For (εις). As often in N.T.