Murray on justification and works

In his commentary on Romans, John Murray addresses justification and works, not for the first time nor the last I'm sure, when considering Romans 2:12-16 which reads as follows;

12 For all who have sinned without the law will also perish without the law, and all who have sinned under the law will be judged by the law. 13 For it is not the hearers of the law who are righteous before God, but the doers of the law who will be justified. 14 For when Gentiles, who do not have the law, by nature do what the law requires, they are a law to themselves, even though they do not have the law. 15 They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them 16 on that day when, according to my gospel, God judges the secrets of men by Christ Jesus.

Murray writes, "Believers are justified by faith alone and they are saved by grace alone. But two qualifications need to be added to these propositions. (a) They are never justified by faith that is alone. (b) In salvation we must not so emphasize grace that we overlook the salvation itself. The concept of salvation involves what we are saved to as well as what we are saved from. We are saved to holiness and good works (cf. Eph. 2:10). And holiness manifests itself in good works." (79)