John H. Gerstner (1914-1996) was professor of Church History at Pittsburgh Theological Seminary and Knox Theological Seminary. He wrote in his book, The Problem of Pleasure: Why Good Things Happen to Bad People, that only in the Gospel of Jesus Christ can divine justice and divine mercy meet.
Only the Christian gospel presents….a way in which justice and mercy kiss each other…First, Christianity confirms the fact that justice must be satisfied. Sin must be condemned according to its demerit. This means eternal doom. The sinner must be damned because God must be inexorably holy and just. His all-powerful Being must vindicate His all-holy Being. Christianity never compromises the ever-blessed purity and excellency of the divine nature. Second, Christianity alone finds a way to satisfy infinite justice and provide infinite mercy at the same time. What no other religion has dreamed of, Jesus Christ has accomplished. He underwent the infinite wrath of God against sin and lived to bestow His mercy on the damned sinners for whom He died. The infinite Son of God took upon Himself a human nature in which He underwent the full fury of the divine wrath. The omnipotent God satisfied His violated holiness by punishing sin completely in His blessed Son, who “became sin” for His people. The justice of God was vindicated in full in the substitute, His own Son, our Saviour dear. He survived that awful vengeance and rose victor over the grave by the power of His own divinity. Now He offers to every sin-sick and “pleasure”- burdened soul an everlasting mercy. Perfect mercy and perfect justice in the gospel of the crucified, (pg. 24-25).