The Catechism of the Catholic Church supports that proposition, but here is a scripture that gives basis for this teaching
“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.) 16 This will take place on the day when God judges people’s secrets through Jesus Christ, as my gospel declares.” Romans 2:14-16
Paragraphs
1776 “Deep within his conscience man discovers a law which he has not laid upon himself but which he must obey. Its voice, ever calling him to love and to do what is good and to avoid evil, sounds in his heart at the right moment… For man has in his heart a law inscribed by God… His conscience is man’s most secret core and his sanctuary. There he is alone with God whose voice echoes in his depths.”<47>
1777 Moral conscience,<48> present at the heart of the person, enjoins him at the appropriate moment to do good and to avoid evil. It also judges particular choices, approving those that are good and denouncing those that are evil.<49> It bears witness to the authority of truth in reference to the supreme Good to which the human person is drawn, and it welcomes the commandments. When he listens to his conscience, the prudent man can hear God speaking.
1778 Conscience is a judgment of reason whereby the human person recognizes the moral quality of a concrete act that he is going to perform, is in the process of performing, or has already completed. In all he says and does, man is obliged to follow faithfully what he knows to be just and right. It is by the judgment of his conscience that man perceives and recognizes the prescriptions of the divine law:
vatican.va/archive/ccc_css/archive/catechism/p3s1c1a6.htm
1795 “Conscience is man’s most secret core, and his sanctuary. There he is alone with God whose voice echoes in his depths” (GS 16).
