Penal substitution

Penal substitution (sometimes, esp. in older writings, called forensic theory) is a theory of the atonement within Christian theology, developed with the Reformed tradition. It argues that Christ, by his own sacrificial choice, was punished (penalised) in the place of sinners (substitution), thus satisfying the demands of justice so God can justly forgive the sins. It is thus a specific understanding of substitutionary atonement, where the substitutionary nature of Jesus' death is understood in the sense of a substitutionary punishment.

Penal substitution derives from the idea that divine forgiveness must satisfy divine justice, that is, that God is not willing or able to simply forgive sin without first requiring a satisfaction for it. It states that God gave himself in the person of his Son, Jesus Christ, to suffer the death, punishment and curse due to fallen humanity as the penalty for our sin.

Important theological concepts about penal substitution depend on the doctrine of the Trinity. Those who believe that Jesus was himself God, in line with the doctrine of the Trinity, believe that God took the punishment upon himself rather than putting it on someone else. In other words, the doctrine of union with Christ affirms that by taking the punishment upon himself Jesus fulfils the demands of justice not for an unrelated third party but for those identified with him. If, in the penal substitution understanding of the atonement, the death of Christ deals with sin and injustice, his resurrection is the renewal and restoration of righteousness. Key biblical references upon which penal substitution is based include:

It is debated if the Church Fathers subscribed to this doctrine, including Justin Martyr c. 100-165, Eusebius of Caesarea c. 275-339, Athanasius c. 300-373 and Augustine of Hippo 354-430 (see Early Church, below). Although penal substitution is often associated with Anselm of Canterbury, he predates its formal development within later Reform theology. It is therefore doubted even among Reform theologians whether his 'satisfaction' theory is strictly equivalent.

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