Romans 11:24

11:24 For if you were cut off from what is by nature a wild olive tree, and grafted, contrary to nature, into a cultivated olive tree, how much more will these natural branches be grafted back into their own olive tree?

Romans 11:21

11:21 For if God did not spare the natural branches, perhaps he will not spare you.

Romans 2:27

2:27 And will not the physically uncircumcised man who keeps the law judge you who, despite the written code and circumcision, transgress the law?

Romans 1:26

1:26 For this reason God gave them over to dishonorable passions. For their women exchanged the natural sexual relations for unnatural ones,

Romans 2:14

2:14 For whenever the Gentiles, who do not have the law, do by nature the things required by the law, these who do not have the law are a law to themselves.