These three quotes from the book ONE show what's good about Good Friday:
"Man's debt to God according to His judgment was death; therefore, Jesus Christ needed to die in order to pay off man's debt."
"The judgment for breaking God's law is the curse of death. God's law would not have been satisfied unless man died. Man's sin was a capital offense . . . Since the sentence was the death of man, a sinless man who wasn't under the curse of death had to die. Jesus Christ paid that price and the ransom to release man from this curse of death. Because Jesus is both God and man, He can legally obtain eternal redemption. As a man, He has human blood to die for man's sins; as God His blood has eternal value and is thus able to pay for the sins of all mankind."
"Jesus Christ has paid off mankind's debt of sin in full through His death; therefore, God, according to His righteous judgment, is required to justify all those having the faith of Jesus. This justification that believers have received from God is not because of any effort to fulfill God's law."