Salvation Explained Part 5 - What is grace and justification?

Finally, we examine this "Grace matter" which has confused a lot of believers. We ask important questions like: Did God change and become gracious in the New Testament? What really is God's grace? What is justification and are we justified? What is the basis of righteousness and why? What's the relationship between God's grace and our justification? Can God's grace really help me live righteously? How do I enjoy my realities in Christ?