I'd like to know the specifics...
One of your errors asserts that these people...
Romans 1:8 First, I thank my God through Jesus Christ for you all, that your faith is spoken of throughout the whole world.
Are these people...
Romans 2:17 Behold, thou art called a Jew, and restest in the law, and makest thy boast of God,
Clearly, they are not...
Romans 2:23 Thou that makest thy boast of the law, through breaking the law dishonourest thou God? 2:24 For the name of God is blasphemed among the Gentiles through you, as it is written. 2:25 For circumcision verily profiteth, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision.
That tells me your basic study approach is off.