High Quality Content by WIKIPEDIA articles! 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.