Ashes Represent Purification
The second symbol that the ashes represent during Lent is purification.
Ashes were used in purification rituals in the Old Testament. The ashes left over from an animal sacrifice were then sprinkled on a person to purify them from sin.
But we have the blood of Christ, which does what the ashes were meant to do in the old times. The book of Hebrews explains it clearly: "The blood of goats and bulls and the ashes of a heifer sprinkled on those who are ceremonially unclean sanctify them so that they are outwardly clean. How much more, then, will the blood of Christ, who through the eternal Spirit offered Himself unblemished to God, cleanse our consciences from acts that lead to death, so that we may serve the living God!" (Hebrews 9:13-14)
Outward Versus Inward Cleansing
The writer to the Hebrews makes a distinction: the Old Testament ritual of applying ashes made people outwardly clean, but the blood of Christ cleanses us inwardly.
In the Old Testament it was a "show" more than anything: my heart hasn't changed but I am forgiven because the bull or heifer died in my place and shed its blood.
But then Jesus came and shed His blood as the Lamb of God, and His blood cleanses my conscience of guilt, so that I may serve God! Not so that I may continue in the acts that lead to death.
Now no animal sacrifices need to be made to God anymore, because Christ's blood atones for our sins, and changes our hearts!
The True Power of Christ's Blood
When you receive the ashes tomorrow, there is no power in the ashes themselves. We are not purified by ash, but we are purified by the blood of Jesus. As we are sprinkled in the blood He shed on the cross, we are purified.
Let the ashes, this Lent, be symbolic of Christ's sacrifice, which purifies us.
The ashes of Ash Wednesday symbolise purification, pointing us to Christ's blood that cleanses us inwardly, not just outwardly.