From Fifty Reasons Why Jesus Came to Die, by John Piper...
#16 To Give Us a Clear Conscience
"How much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God." (Hebrews 9:14)
Some things never change. The problem of a dirty conscience is as old as Adam and Eve. As soon as they sinned, their conscience was defiled. Their sense of guilt was ruinous. It ruined their relationship with God—they hid from him. It ruined their relation to each other—they blamed. It ruined their peace with themselves—for the first time they saw themselves and felt shame.
All through the Old Testament, conscience was an issue. But the animal sacrifices themselves could not cleanse the conscience. “Gifts and sacrifices are offered that cannot perfect the conscience of the worshiper, but deal only with food and drink and various washings, regulations for the body imposed until the time of reformation” (Hebrews 9:9-10). As a foreshadowing of Christ, God counted the blood of the animals as sufficient for cleansing the flesh—the ceremonial uncleanness, but not the conscience.
No animal blood could cleanse the conscience. They knew it (see Isaiah 53 and Psalm 51). And we know it. So a new high priest comes—Jesus the Son of God—with a better sacrifice: himself. "How much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God” (Hebrews 9:14).
The animal sacrifices foreshadowed the final sacrifice of God’s Son, and the death of the Son reaches back to cover all the sins of God’s people in the old time period, and forward to cover all the sins of God’s people in the new time period.
So here we are in the modern age—the age of science, Internet, organ transplants, instant messaging, cell phones—and our problem is fundamentally the same as always: Our conscience condemns us. We don’t feel good enough to come to God. And no matter how distorted our consciences are, this much is true: We are not good enough to come to him.
We can cut ourselves, or throw our children in the sacred river, or give a million dollars to the United Way, or serve in a soup kitchen on Thanksgiving, or perform a hundred forms of penance and self-injury, and the result will be the same: The stain remains, and death terrifies. We know that our conscience is defiled—not with external things like touching a corpse or eating a piece of pork.
Jesus said it is what comes out of a person that defiles, not what goes in (Mark 7:15-23). We are defiled by pride and self-pity and bitterness and lust and envy and jealousy and covetousness and apathy and fear—and the actions they breed. These are all “dead works.” They have no spiritual life in them. They don’t come from new life; they come from death, and they lead to death. That is why they make us feel hopeless in our consciences.
The only answer in these modern times, as in all other times, is the blood of Christ. When our conscience rises up and condemns us, where will we turn? We turn to Christ. We turn to the suffering and death of Christ—the blood of Christ. This is the only cleansing agent in the universe that can give the conscience relief in life and peace in death.
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