How can this be since we Gentiles are not biologically connected to Abraham?
In the book of Romans, Paul makes it clear that anyone who trusts in God is of the seed of Abraham.
Now, God told Abraham that he would be the father of many nations with too many people to count such as the stars of heaven. But Israel is but one nation so how is Abraham the father of many nations as God promised?
God was talking about those who are the spiritual seed of Abraham. Those that are deemed righteous by God through their trust in the faith of His Son Jesus. In having this trust, God puts the righteousness of Jesus and his perfect faith on us. Our own faith is too fickle to ever be of any real use so we should just stop talking about it.
Remember, Abraham was deemed righteous by God because he believed God and trusted in what God promised him. That was done before Abraham was circumcised and it was after about 29 years that he was circumcised as a seal of the covenant of faith and trust in God. And the Law of Moses was not given until some 600 years after Abraham, so the Law was nothing that Abraham knew about or had to follow in his time to be considered righteous.
For the Gentiles, our uncircumcism is counted as circumcism because of our belief and trust in God just as Abraham was.
Because Abraham is also the spiritual father to gentile Believers in Christ, the gentile Believers are as much legitimate seed of Abraham as are Jews; just in a slightly different sense that doesn’t involve membership in the Jewish nation or their requirement to be physically circumcised.
Since we have indeed become righteous by our trust in God, then we need to maintain our newly found “peace” with God “through our Lord, Jesus the Messiah”. Let’s see how we do that next in another post which will be titled “Dying and being buried with Christ”.