So I would like to know what was accomplished and what was finished. what was 'performed'?
Jesus' Passive and Active Obedience was Finished, Performed, and Accomplished, in His part of the Eternal Covenant Agreement, Among the GODHEAD.
What was paid? Is it reasonable to argue that nothing was accomplished/finished/performed/paid until the Lord Jesus died?
Sin debt was paid for The Godhead's elect. It is reasonable to argue that His payment had not yet beed technically ratified, as a hair that is unreasonable to split.
Of course, not only had He not Chronologically died, and Confirmed this Testament, whether or not, "it is Finished", was spoken literally with His last breath, it is Logically impossible that Jesus could have even contemplated jumping off the cross prior to His death and nullifying His ultimately assured complete Finished Work to be Accomplished, WITH ALLPOWERFULLY EXECUTED SUCCESS, as the Surety and Testator of the Eternal Covenant of Grace.
Since, as God, Jesus had just said, "it is Finished" and God can not lie.
"Christ as a Surety, engaged to pay the debts of his people, and satisfy for the wrong and injury done by them."
"...this may be illustrated by the instance of the apostle Paul engaging for Onesimus;
"which is thus expressed, "If he hath wronged thee, or oweth thee ought, put that on my account; I Paul, have written it with mine own hand, I will repay it", (Philem. 1:18, 19).
"Sin is a wrong and injury done to divine justice, and to the holy law of God, broken by it;
"which Christ undertook to satisfy for; and sins are debts; see (Matthew 6:12) compared with (Luke 11:4) not proper ones, for then they might be committed with impunity, since it is right and commendable to pay debts: but in an improper sense, as debts oblige to payment, so sins to punishment;
"even to endure the curse of the law, and death eternal, the sanction of it: these debts, or sins, are infinite objectively, as they are contracted and committed against an infinite being, and require punishment of a creature ad infinitum;
"and therefore not to be paid off, or answered, by a finite creature;
"but Christ being an infinite Person, as God, was able to pay off those debts, and answer for those sins, and engaged to do it, and has done it.
"There is a twofold debt paid by Christ, as the Surety of his people; the one is a debt of obedience to the law of God;
"this he engaged to do, when he said, "Lo, I come to do thy will"; thy law is within my heart: and accordingly
he was made under the law, and yielded perfect obedience to it, by which his people are made righteous;
"and the other is a debt of punishment, incurred through failure of obedience in them;
"
the curse of the law he has endured, the penalty of it, death; and by paying both these debts, the whole righteousness of the law is fulfilled in his people, considered in him their Head and Surety."
Then, what happened?
He had also not been Separated in the Spirit, from His body God the Father had Elected and Prepared for Him, and then, Returned to Heaven, as God Who is Spirit, had not yet died, or been buried, and had not Resurrected from the dead, or Ascended back to Heaven, to "Fullfil" His Position as the Federal Head of His Elect and Mediator.
Resurrected from the dead.
"In consequence of Christ's covenant engagements and performances,
when he rose from the dead, he rose not as a private Person, but as a public Person, as the head and representative of all those for whom he obeyed and suffered;
"and therefore they are said to be quickened and raised together with him, as they were then also justified in him, when he himself, as their Head and Surety was, #Eph 2:5,6 Col 3:1 1Ti 3:16.
Ascended back to Heaven, as Mediator.
"Yea,
Christ is also gone to heaven, not only as the Forerunner of his people, but as their Head and Representative;
"he has taken possession of heaven in their name,
appears in the presence of God for them, and represents them, as the high priest did the children of Israel, in the holy of holies; and hence they are said to be made to sit together in heavenly places "in Christ Jesus", #Eph 2:6."
"CHRIST, THE TESTATOR OF THE COVENANT.
1. First, The covenant of grace bears the name, and has the nature of a testament: it is often called
the new and better testament, as administered under the gospel dispensation, (Matthew 26:28; Heb. 7:22, 9:15) in distinction from the former:
it is called a testament, in allusion to the last will and testament of men.
"And,
1a. Because it is the will of God himself, and not another;
'the will of him that is sovereign and absolute, who does according to his will in heaven and in earth, in nature, providence, and grace.
"The covenant is founded on the will of God, and is the pure effect of it; he was not obliged to make it;
"he freely and of his own accord came into it;
"so all the contracting parties in it,
(the Godhead) as has been before observed.
A man's will or testament ought to be voluntary; he is not to be forced nor drawn, nor pressed to make it, contrary to his inclination; or otherwise it is not his own will.
"
This will, or testament, of Jehovah, is an ancient one, it was made in eternity;
"it is called an everlasting covenant, or testament; not only because it always continues, and will never become null and void, but because it is from everlasting;
"the bequests and donations made in it were made before the world began (2 Tim. 1:9).
"Who hath saved us, and called us with an holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus before the world began,"
It is a will or testament that is unalterable; "Though it be but a mans covenant", or testament, "yet if it be confirmed" by his own handwriting and seal, and especially by his death, "no man disannulleth or addeth thereunto" (Gal. 3:15).
"The covenant of grace is ordered in all things, and sure; this testament, or will, is founded upon the immutability of the divine counsel;
"so that the heirs of promise, the legatees in it, may have strong consolation, and be fully assured of enjoying their legacies in it;
"which are the sure mercies of David, of David's Son and Antitype, as all the promises of it are Yea and Amen in him.
"To all wills there are commonly witnesses, and often three, and in some cases three are required.
"Now as God sware by himself, because he could sware by no greater;
"so because no other and proper witnesses could be had, to witness this will made in eternity, God himself, or the three divine Persons, became witnesses to it, the Three that bare record in heaven, the Father, the Word, and the Holy Ghost (1 John 5:7).
( In case you ever wonder why Satan has put so much effect into trying to remove this verse from our Canon!)