What did the Law do for man?
The Law served as a mirror that showed man his utter sinfulness and his helplessness. It did not bring the indwelling Holy Spirit, which the context says is something totally different. Its purpose was to reveal man's condition, not to indwell him.
Les explains that the Law was just the mirror that showed man his utter sinfulness and his helplessness. The indwelling Holy Spirit, however, is something totally different. The Law did not provide that Spirit. The context then moves to Ephesians 1, where God sent His own Son in the likeness of sinful flesh. Christ came to condemn the old Adam and the flesh, dealing with man at his level.