O Sweet Exchange!

"In His mercy He took up the burden of our sins. He Himself gave up His own Son as a ransom for us-- the Holy One for the unjust, the innocent for the guilty, the righteous one for the unrighteous, the incorruptible for the corruptible, the immortal for the mortal. For what else could cover our sins except for His righteousness? In whom we, lawless and impious as we were, be made righteous except in the Son of God alone? O sweet exchange! O unfathomable work of God! O blessings beyond all expectation! The sinfulness of many is hidden in the Righteous One. While the righteousness of the One justifies the many that are sinners." - Letter to Diognetus.