The man who wrote this said of himself elsewhere, “concerning the righteousness which is in the law, blameless” (Phil. 3:6). Earlier in Paul’s life his righteousness appeared to him, and maybe to others, as good enough for God, but eventually he learned by bitter experience that he was a sinner like everyone else: “all have sinned and fall short of the glory of God” (Rom. 3:23).

Saul—as he was called then—was not so unusual, just more impressive than most of us at trying to justify himself before God. But this is the delusion of man’s religion. When the Philippian jailer tried to adopt it by asking Paul and Silas, “What must I do to be saved?” they replied, “Believe on the Lord Jesus Christ, and you will be saved” (Acts 16:30–31).

Only God’s righteousness will do, and this is available in His Son, the Lord Jesus, who dealt with the matter of sin perfectly when He died on the cross. But why does Paul call the gospel “the power of God to salvation”? Simply because it presents God’s righteousness as the only basis on which He saves, and all we have to do to benefit from its message is receive it as true. This is what the apostle means by “faith” the first time he uses it in verse 17: he means the principle of faith.

The Lord Jesus said to the Jews, “This is the work of God, that you believe in Him whom He sent” (Jn. 6:29). Sadly, it seems that many of them did not do so. But what about you? Have you believed on the Lord Jesus? If not, do so now and you will be saved. This is what Paul means by his second reference to “faith”: your faith exercised in the Lord Jesus in response to God’s wonderful offer of salvation.