If the task of Christology is to make intelligible the Christian faith that Jesus of Nazareth, a historical person, is Christ as the centre of all human history and the final and full revelation of God to humanity—then Rahner feels that within "the contemporary mentality which sees the world from an evolutionary point of view" the person of Christ should not be emphasised in his unique individuality whilst ignoring any possibility of combining the event of Christ with the process of human history as a whole. In fact, it appears there are some limitations of classic Christological formula suggested by the Council of Chalcedon (AD 451) which affirms "one identical Son, our Lord Jesus Christ ... perfect both in his divinity and in his humanity ... two natures without any commingling or change or division or separation ... united in one person." Moreover, the Chalcedon formula adopts philosophical concepts such as "nature" and "hypostatic union" which are no longer used to explain and interpret religious experiences.