The Son of God, the second person in the Trinity, being truly and eternally God, of one substance and equal with the Father, when the fullness of time came, took upon himself mankind’s nature, with all the essential properties and common infirmities of it, yet without sin, being conceived by the power of the Holy Spirit in the womb of the virgin Mary, and of her substance. Thus two whole, perfect, and distinct natures, the Godhead and the manhood, were inseparably joined together in one person, without conversion, composition, or confusion. This person is truly God and truly man, and yet is one Christ, the only mediator between God and man.
(WCF 8.2)
For the past couple of weeks we have been in chapter 8 of the Westminster Confession. Chapter 8 is concerned with a particular office and that is of the mediator. WCF 8.1 simply stated that we need a mediator (someone to stand between all sinful humanity and All Mighty God) and that that mediator is Jesus Christ. This week, the confession concerns us with just who Jesus Christ is.
We start with His eternal nature. Jesus is The Son of God, the second person in the Trinity, being truly and eternally God, of one substance and equal with the Father. Drawing on Jn 1:1,14, 1 Jn 5:20, Phil 2:6, Gal 4:4 and language employed by the Nicene Father’s, our attention is instantly drawn to the fact that God’s chosen mediator is none other than God’s Son. But this is the thing, His sonship doesn’t make Him any less deity than the Father, no, they are of one substance and equal in glory.
Let’s briefly think about what is being said here. The Son isn’t the Father and the Father isn’t the Son, but they are both fully and properly God. This is why the language of ‘substance’ and ‘person’ is helpful here. God is one in ‘substance’ but not in ‘person’, no there are three distinct persons in the Godhead or what we call ‘The Trinity’ (one God in three Persons). Much could be said here, but what is important is this - the mediator that God chose and ordained (WCF 8.1), was and is none other than the Son of God Himself.
And so how did He come to take this role? Well, the confession states that when the fullness of time came, (He) took upon himself mankind’s nature, with all the essential properties and common infirmities of it, yet without sin, being conceived by the power of the Holy Spirit in the womb of the virgin Mary, and of her substance. To put that another way, the third person of the Trinity, conceived Jesus of Nazareth in the human body of Mary (Lk 1:27, 31-35; Gal 4:4). This is what we call the doctrine of the incarnation whereby we understand that The Spirit ‘joined’ the substance of God to the substance of humanity. This is where we get the saying in the Nicene Creed that Jesus is ‘very God and very man’. Are we to fully comprehend this? No, it’s as the 4th century theologian Augustine once quipped, ‘deny the trinity and you deny salvation, understand the trinity and deny sanity.’
This is truly a mystery, but the point is simple. God from eternity past didn’t plan to have sinful mediators stand between Himself and us, but His own Son for all time. And because God became very much human in Jesus (yet is sinless), He really can stand for all time as our merciful mediator drawing us to absolute holiness, yet knowing what we’re facing (Heb 2:14-17; 4:15). Or as the confession helpfully sums it up, Thus two whole, perfect, and distinct natures, the Godhead and the manhood, were inseparably joined together in one person, without conversion, composition, or confusion. This person is truly God and truly man, and yet is one Christ, the only mediator between God and man.
We have a God from eternity past that planned to have a real relationship with us. We are all sinful, He is All Mighty, yet He made a way for that relationship to be made possible and that is through His Son Jesus Christ, Immanuel, God with us.