The Lord Jesus, in his human nature thus united to the divine, was sanctified and anointed with the Holy Spirit beyond measure, having in him all the treasures of wisdom and knowledge. It pleased the Father that all fullness should dwell in him, for the purpose that, being holy, harmless, undefiled, and full of grace and truth, he might be thoroughly equipped to carry out the office of a mediator, and a payment for them. He did not take this office to himself, but was called to it by his Father, who put all power and judgment into his hand, and gave him the command to carry it out.
(WCF 8.3)
God created us to glorify Him and to enjoy Him forever (WSC 1), yet because of our first parent’s sin and the ramifications thereof, our coming to God off our own backs was completely and utterly derailed (Gen 3:16-19, Rom 5:12-21 c.f. Rom 1:18-25). God knew this to be the case when He first created us, He knew that we would be tempted and fall into rebellion (1 Jn 3:20). That’s why Jesus was the willing and prepared sacrifice ‘from before the foundation of the world’ (Jn 1:29, Rev 13:8). In other words, Christ’s substitutionary atonement wasn’t an after thought, but a planned and purposed event in history (Gen 50:20, Acts 2:23)
In Old Testament times, the people of God looked forward to Christ’s coming. They had Him in the promises, types and shadows (Heb 8:5-6). The main place they ‘saw’ Jesus in these things was in the priesthood and temple system. There were lambs, there was blood and there was substitutionary sacrifice on behalf of the sinner (Lev 6:24-30 c.f Ex 12:1-28, 43-51). Yet, these things only looked forward to what Jesus would do, as He was the substance of these things, and the elect knew it (Isa 52:13-53:12, Heb 10:1-4).
Now I mention this, because the temple was hugely significant. If people wanted to meet with God, they had to go to Israel and they had to go to a priest to stand on their behalf before the Alta - not even the priest was allowed to enter the most holy place - that was something reserved for the High Priest, and that being only once a year on the Day of Atonement (Lev 16:1-34, 23:26-28). All this to say, God’s presence dwelt in the temple, it was the meeting place of the eternal with the temporal - a place where God condescended to meet with sinful humanity, which was a type of ministry as to what Jesus would be for His people (Jn 2:19-21, Heb 9:11), or as the Confession puts it, The Lord Jesus, in his human nature thus united to the divine, was sanctified and anointed with the Holy Spirit beyond measure, having in him all the treasures of wisdom and knowledge.
Simply stated, Jesus became the focal point of meeting with God. He is what the temple, sacrificial system and priesthood was all about (Lk 24:44, Heb 9:12-14). That was the place where one would have a priest ‘mediate’ on behalf of them before our Holy God. The Confession puts it this way, It pleased the Father that all fullness should dwell in him, for the purpose that, being holy, harmless, undefiled, and full of grace and truth, he might be thoroughly equipped to carry out the office of a mediator, and a payment for them.
And thus Jesus being fully man and fully God at the very same time, He was the perfect sacrifice and is the perfect mediator, who - till this very day, is in Heaven interceding on behalf of His blood purchased people (Heb 4:14-16). Incredibly this honour was something that He accepted in full submission to the Father, who bestowed it on Him, as we read, He did not take this office to himself, but was called to it by his Father, who put all power and judgment into his hand, and gave him the command to carry it out.
God eternal in Father, Son and Spirit chose a people from before time to save and secure by sacrificial the work of Jesus Christ (8:29-30, Eph 1:4-6), whom the Father sent and the Spirit led so that we might be rescued for all eternity. This isn’t a hope we have just in the future, but because of God’s work on behalf of His people - this is something we posses now that can never be taken away. Gone are the days of going to the temple and come are the days of refreshing, where all the people of God don’t have to wait for a day, but are invited anytime to speak to our Father in Heaven, through Jesus Christ by the power of the Holy Spirit.