As the Old Testament high priest emerged from the Holy of Holies, he stood as a symbol to the people of God's mercy toward them. The very fact of his being alive signified that God had accepted their sacrifice. He then became the ever-living witness before them of the mercy of God. Every time they saw him, they could remember that God was dealing with them by His mercy.

In the same way believers today stand as living witnesses to the world of God's mercy. When people look at Christians, they are seeing a living demonstration of God's mercy. God has not given us what we deserve and has given us what we do not deserve.
Now thanks be unto God, which always causeth us to triumph in Christ, and maketh manifest the savour of his knowledge by us in every place. For we are unto God a sweet savour of Christ, in them that are saved, and in them that perish: To the one we are the savour of death unto death; and to the other the savour of life unto life. And who is sufficient for these things?
(2 Cor. 2:14-16)
We are the manifest "savour of his knowledge to the world." Unto God we are the sweet savour of Christ. To the world we are the savour of death.
In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead. And you, being dead in your sins and the uncircumcision of you flesh, hath he quickened together with him, having forgiven you all trespasses; Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross; And having spoiled principalities and powers, he made a shew of them openly, triumphing over them in it.
(Col. 2:11-15)

I am crucified with Christ: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.
(Gal. 2:20)
We are examples to the world of both death and life: death to the things of the world, life to the things of God. We have been taken out of the control of the dominion of darkness and have been translated into the Kingdom of God.

God has always given to the world a living witness of Himself. It is therefore not strange to view ourselves as a living witness of God's mercy.

In Acts 1:8, Jesus told His followers that when the Holy Spirit came upon them, they would be witnesses. On the day of Pentecost, they became witnesses of the power of God when they were filled with the Holy Spirit and began to speak with other tongues as the Spirit gave them utterance (Acts 2:2-4).

We believers are living witnesses of God's mercy, for all that God is and does stems from love, and mercy is one of the primary by-products of love.

Source: The Force Of Mercy by Buddy Harrison & Dr. Michael Landsman.
Excerpt permission granted by Harrison House Publishers