I mentioned earlier today that I was reading a book titled, "Reformation Readings of Paul: Explorations in History and Exegesis" Edited By Michael Allen and Jonathan A. Linebaugh. Today I was read or had been reading in this book Chapter 8 'The Text of 1 & 2 Corinthians and the Theology of Calvin' essay by Dane C. Ortlund. In this chapter Ortlund quotes from Calvin's commentary in First and Second Corinthians, so I got out my volume of this commentary to read the quotes. I came across in Calvin's Commentary on Second Epistle To The Corinthians that goes along with what I have been writing about today/the mercy of God/Christ being the mercy seat. I want to quote Calvin's comments on 2 Corinthians 5:18,19 "Now all things are of God, who has reconciled us to Himself through Jesus Christ, and has given us the ministry of reconciliation, that is, that God was in Christ reconciling the world to Himself, not imputing their trespasses to them, and has committed to us the word of reconciliation".
"18. All things are of God. He means, all things that belong to Christ's kingdom. "If we would be Christ's, we must be regenerated by God. Now that is no ordinary gift." He does not, therefore, speak here of creation generally; but of the grace of regeneration, which God confers peculiarly upon his elect, and he affirms that it is of God -- not on the ground of his being the Creator and Artificer of heaven and earth, but inasmuch as he is the new Creator of the Church, by fashioning his people anew, according to his own image. Thus all flesh is abased, and believers are admonished that they must now live to God, inasmuch as they are a new creature. (2 Corinthians 5:17.) This they cannot do, unless they forget the world, as they are also no longer of the world, (John 17:16,) because they are of God
Who hath reconciled us Here there are two leading points -- the one relating to the reconciliation of men with God; and the other, to the way in which we may enjoy the benefit of this reconciliation. Now these things correspond admirably with what goes before, for as the Apostle had given the preference to a good conscience above every kind of distinction, (2 Corinthians 5:11,) he now shows that the whole of the gospel tends to this. He shows, however, at the same time, the dignity of the Apostolical office, that the Corinthians may be instructed as to what they ought to seek in him, whereas they could not distinguish between true and false ministers, for this reason, that nothing but show delighted them. Accordingly, by making mention of this, he stirs them up to make greater proficiency in the doctrine of the gospel. For an absurd admiration of profane persons, who serve their own ambition rather than Christ, originates in our not knowing, what the office of the preaching of the gospel includes, or imports.
I now return to those two leading points that are here touched upon. The first is -- that God hath reconciled us to himself by Christ This is immediately followed by the declaration -- Because God was in Christ, and has in his person accomplished reconciliation. The manner is subjoined -- By not imputing unto men their trespasses Again, there is annexed a second declaration -- Because Christ having been made a sin-offering for our sins, has procured righteousness for us. The second part of the statement is -- that the grace of reconciliation is applied to us by the gospel, that we may become partakers of it. Here we have a remarkable passage, if there be any such in any part of Paul's writings. Hence it is proper, that we should carefully examine the words one by one.
The ministry of reconciliation Here we have an illustrious designation of the gospel, as being an embassy for reconciling men to God. It is also a singular dignity of ministers -- that they are sent to us by God with this commission, so as to be messengers, and in a manner sureties.  This, however, is not said so much for the purpose of commending ministers, as with a view to the consolation of the pious, that as often as they hear the gospel, they may know that God treats with them, and, as it were, stipulates with them as to a return to his grace. Than this blessing what could be more desirable? Let us therefore bear in mind, that this is the main design of the gospel -- that whereas we are by nature children of wrath, (Ephesians 2:3,) we may, by the breaking up of the quarrel between God and us, be received by him into favor. Ministers are furnished with this commission, that they may bring us intelligence of so great a benefit, nay more, may assure us of God's fatherly love towards us. Any other person, it is true, might also be a witness to us of the grace of God, but Paul teaches, that this office is specially intrusted to ministers. When, therefore, a duly ordained minister proclaims in the gospel, that God has been made propitious to us, he is to be listened to just as an ambassador of God, and sustaining, as they speak, a public character, and furnished with rightful authority for assuring us of this.
19. God was in Christ. Some take this as meaning simply -- God reconciled the world to himself in Christ; but the meaning is fuller and more comprehensive -- first, that God was in Christ; and, secondly, that he reconciled the world to himself by his intercession. It is also of the Father that this is affirmed; for it were an improper expression, were you to understand it as meaning, that the divine nature of Christ was in him.  The Father, therefore, was in the Son, in accordance with that statement --
I am in the Father, and the Father in me. (John 10:38.)
Therefore he that hath the Son, hath the Father also. For Paul has made use of this expression with this view -- that we may learn to be satisfied with Christ alone, because in him we find also God the Father, as he truly communicates himself to us by him. Hence the expression is equivalent to this -- "Whereas God had withdrawn to a distance from us, he has drawn near to us in Christ, and thus Christ has become to us the true Emmanuel, and his coming is God's drawing near to men."
The second part of the statement points out the office of Christ -- his being our propitiation, (1 John 2:2,) because out of Him, God is displeased with us all, inasmuch as we have revolted from righteousness.  For what purpose, then, has God appeared to men in Christ? For the purpose of reconciliation -- that, hostilities being removed, those who were aliens, might be adopted as sons. Now, although Christ's coming as our Redeemer originated in the fountain of Divine love towards us, yet until men perceive that God has been propitiated by the Mediator, there must of necessity be a variance remaining, with respect to them, which shuts them out from access to God. On this point we shall speak more fully ere long.
Not imputing to them. Mark, in what way men return into favor with God -- when they are regarded as righteous, by obtaining the remission of their sins. For so long as God imputes to us our sins, He must of necessity regard us with abhorrence; for he cannot be friendly or propitious to sinners. But this statement may seem to be at variance with what is said elsewhere -- that, we were loved by Him before the creation of the world, (Ephesians 1:4,) and still more with what he says, (John 3:16,) that the love, which he exercised towards us was the reason, why He expiated our sins by Christ, for the cause always goes before its effect. I answer, that we were loved before the creation of the world, but it was only in Christ In the mean time, however, I confess, that the love of God was first in point of time, and of order, too, as to God, but with respect to us, the commencement of his love has its foundation in the sacrifice of Christ. For when we contemplate God without a Mediator, we cannot conceive of Him otherwise than as angry with us: a Mediator interposed between us, makes us feel, that He is pacified towards us. As, however, this also is necessary to be known by us -- that Christ came forth to us from the fountain of God's free mercy, the Scripture explicitly teaches both -- that the anger of the Father has been appeased by the sacrifice of the Son, and that the Son has been offered up for the expiation of the sins of men on this ground -- because God, exercising compassion towards them, receives them, on the ground of such a pledge, into favor. 
The whole may be summed up thus: "Where sin is, there the anger of God is, and therefore God is not propitious to us without, or before, his blotting out our sins, by not imputing them. As our consciences cannot apprehend this benefit,  otherwise than through the intervention of Christ's sacrifice, it is not without good reason, that Paul makes that the commencement and cause of reconciliation, with regard to us.
And hath committed to us. Again he repeats, that a commission has been given to the ministers of the gospel to communicate to us this grace. For it might be objected, "Where is Christ now, the peacemaker between God and us? At what a distance he resides from us!" He says, therefore, that as he has once suffered,  (1 Peter 3:18,) so he daily presents to us the fruit of his suffering through means of the Gospel, which he designed, should be in the world,  as a sure and authentic register of the reconciliation, that has once been effected. It is the part of ministers, therefore, to apply to us, so to speak, the fruit of Christ's death." John Calvin