Can a good upbringing or a Bible-preaching church keep a person from falling short of God's glory?
No. A good home or a Bible-preaching church cannot prevent anyone from falling short of God's glory. Until God does something, every person remains a sinner and a son of Adam, so all fall short and need God's intervention. Good environments are not enough.
Les explains that verse 23 is the crowning conclusion of everything God has said in the first three chapters, and it applies to everybody, every one of us. He stresses that no matter how good a home you came from or how good a Bible-preaching church you have been in, we still have to recognize that until God does something, we are falling short of the glory of God. We are sinners, we are sons of Adam. Therefore, a good upbringing or a Bible-preaching church does not keep a person from falling short; God Himself must do the necessary work.
For all have sinned, and come short of the glory of God;