Romans 2:14–16

14 When Gentiles who have not the law do by nature what the law requires, they are a law to themselves, even though they do not have the law. 15 They show that what the law requires is written on their hearts, while their conscience also bears witness and their conflicting thoughts accuse or perhaps excuse them 16 on that day when, according to my gospel, God judges the secrets of men by Christ Jesus.