What is religion according to the Bible?
Religion, according to this biblical context, is a compilation of man's efforts to appease a Holy God. It is what man attempts to do to somehow merit favor with God, whether Oriental, Protestant, Catholic, or Jewish. The Jews' religion Paul practiced had nothing of the power of God in it.
Les explains that religion is always a compilation of man's efforts to somehow appease a Holy God. He says this is true whether it is the Oriental religions, Protestantism, Catholicism, or Judaism—religion is what man attempts to do to merit favor with God. Paul wrote of his past manner of living in the Jews' religion, and Les notes that at the time Paul practiced it, during Christ's earthly ministry and shortly after, that religion was all it was: there was nothing of the power of God in it. This contrasts with God's power and the different tack He took after Israel rejected the covenant promises, turning to the Gentiles, as Paul lays out.