The great doctrine, the greatest of all, is this, that God, seeing men to be lost by reason of their sin, hath taken that sin of theirs and laid it upon his only begotten Son, making him to be sin for us, even him who knew no sin; and that in consequence of this transference of sin he that believeth in Christ Jesus is made just and righteous, ya, is made to be the righteousness of God in Christ. Christ was made sin that sinners might be made righteousness. That is the doctrine of the substitution of our Lord Jesus Christ on the behalf of guilty men.
—Charles H. Spurgeon
The Metropolitan Tabernacle, “The Heart of the Gospel,” Sermon 1910, 2 Cor 5:20–21.