Amen, Glen. There is a great difference between the character of Adam living in holy flesh and mature Christians who live in fallen flesh. The only temptation set before Adam was to not eat of the forbidden fruit. Today, we have many temptations and we live in fallen flesh.
"They will have the perfected character of Christ, honed to maturity in righteousness by the persisting humility of an indwelling Saviour; as like-minded with Him..."
Yes, the grace of Christ when taken into the heart brings power to obey all that is revealed. Continual obedience produces strong character. Coupled with a knowledge of God and of sin, the last group of Christians will be able to resist all sin even while living in fallen flesh. Why? Because they know their continual need of an abiding Christ in order to do any good thing. They cling to Christ so they will not deny Him His reward for His suffering. What is that reward? It is seeing Himself reflected in their character.