Promise and Mercy in Messiah

The way both Jews and Gentiles in the church at Rome were to embrace one another is based on what God did in redemptive history: he fulfilled his promise to the patriarchs to send a Redeemer and that same redeemer was the embodiment of mercy to the Gentiles who were just as separated from fellowship with God because of their sins as the Jews were. So both groups in the church are united by a common need and a common hope in God's provision of redemption through his Son.