Westminster Larger Catechism in modern English question number sixty:
Q. 60. Can those who have never heard the gospel and so do not know or believe in Jesus Christ be saved by living according to the light of nature?
A. Those who have never heard the gospel and do not know or believe in Jesus Christ cannot be saved, no matter how diligent they are to frame their lives according to the light of nature or the laws of the religion they profess. There is no salvation in any other but in Christ alone, who is the Savior of His body the church, only.