Today society largely denies or is indifferent to the reality of sin. But at the cross we are confronted with the diabolical nature of sin, which is ugly, real, and costly. It can be removed only by that blood “poured out for the many for the forgiveness of sins” (Matthew 26:28). If there were no sin, it would not have been necessary for Jesus to shed His blood on sinner’s behalf. JTL17 5.1
At Jesus’ death, Satan was stripped of all his demonic power over God’s people, if they placed their trust in the One who brought about that victory. By giving up His life on the cross, Christ crushed the power of Satan and triumphed over the powers of darkness. The one who once boasted that he would “be like the Most High” (Isaiah 14:14) is now made a cosmic spectacle of shame and defeat. Evil no longer holds power over believers, who have passed from the kingdom of darkness to the kingdom of light. Thus, the cross ensures final eschatological victory over Satan, sin, and death. JTL17 5.2
Every believer must affirm and proclaim the “once for all” (Romans 6:10; Hebrews 7:27; 10:10) sacrificial and substitutionary nature of the death of Christ. We are saved to grow in grace by the Christ of the cross. JTL17 5.3