Romans 2:12-15 NIV

[12] All who sin apart from the law will also perish apart from the law, and all who sin under the law will be judged by the law. [13] For it is not those who hear the law who are righteous in God’s sight, but it is those who obey the law who will be declared righteous. [14] (Indeed, when Gentiles, who do not have the law, do by nature things required by the law, they are a law for themselves, even though they do not have the law. [15] They show that the requirements of the law are written on their hearts, their consciences also bearing witness, and their thoughts sometimes accusing them and at other times even defending them.)