Galations 5:6 >For in Christ Jesus neither circumcision nor uncircumcision means anything, but faith working through love. Also Romans 2 & 3 Those are written under the NEW COVENANT. After Jesus fulfilled the Old, we now live under the New. The OLD COVENANT (which was fulfilled by Jesus) was made with Abraham in Genesis 17 - >10 This is My covenant, which you shall keep, between Me and you and your descendants after you: every male among you shall be circumcised. 11 And you shall be circumcised in the flesh of your foreskin, and it shall be the sign of the covenant between Me and you. It says "flesh of your foreskin" pretty clearly. The problem is understanding the Old vs. New Covenant, which is fully explained in the book of Hebrews. Jesus has completely fulfilled the old. The old covenant has no value in Salvation, its purpose was to reveal our sinful condition in comparison to God's law and lead people to Christ - the only one who could take away sin and was resurrected to life.