Who is the testator?

[SteveIndy]

(Heb 9:15) And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.
(Heb 9:16) For where a testament is, there must also of necessity be the death of the testator.
(Heb 9:17) For a testament is of force after men are dead: otherwise it is of no strength at all while the testator liveth.

Are we in agreement that Christ was the testator, the one who actually gave the law on Sinai?

(Rom 7:1) Know ye not, brethren, (for I speak to them that know the law,) how that the law hath dominion over a man as long as he liveth?
(Rom 7:2) For the woman (the Church) which hath an husband (Christ) is bound by the law to her husband so long as he liveth; but if the husband be dead (at Calavary), she is loosed from the law of her husband.
(Rom 7:3) So then if, while her husband liveth, she be married to another man, she shall be called an adulteress: but if her husband be dead, she is free from that law; so that she is no adulteress, though she be married to another man.
(Rom 7:4) Wherefore, my brethren, ye also are become dead to the law by the body of Christ; that ye should be married to another, even to him who is raised from the dead, that we should bring forth fruit unto God.

The Christ who gave the law died and was raised again. The husband who gave the law died and we are to be married to the risen savior.
By means of the cross, we see the love of God for the world displayed. Love is the fulfilling of the law. The law does not fulfill love.
God is love (1John 4:8,16) and love does make a record of sin (1Corinthians 13:5).

The "testator" is the one who writes the will. We have two last will and "testaments" in our Bible. The first last will and testament is the O.T. and of course the second is the N.T. As long as the testator, i.e. the one who writes the will, is alive he has the liberty to amend, rewrite, or throw out what was written first and Christ did exactly that. He re-wrote the "will" and then He died sealing that will forever. For that reason, anyone who stands before the Judge and pleads any argument using the first "will" will not have a leg to stand on because the document is invalid, it is now only used as an illustration to give understanding to the last will.

 

[BobRyan]

The "testator" is the one who writes the will. We have two last will and "testaments" in our Bible. The first last will and testament is the O.T. and of course the second is the N.T. As long as the testator, i.e. the one who writes the will, is alive he has the liberty to amend, rewrite, or throw out what was written first and Christ did exactly that.

A charge he flatly denies in Matthew 5
17 “Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill. 18 For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled. 19 Whoever therefore breaks one of the least of these commandments, and teaches men so, shall be called least in the kingdom of heaven; but whoever does and teaches them, he shall be called great in the kingdom of heaven. 20 For I say to you, that unless your righteousness exceeds the righteousness of the scribes and Pharisees, you will by no means enter the kingdom of heaven.

Thus it is "still a sin to take God's name in vain" even for Christians.
And thus "SIN IS transgression of the LAW" 1 John 3:4 even in the NT.
Thus that same OT LAW that includes the TEN Commandments - still today "condemns all the world" as sinners - Romans 3:19-20
Thus today our faith "Establishes the LAW" rather than making it void Romans 3:31

He re-wrote the "will" and then He died sealing that will forever. For that reason, anyone who stands before the Judge and pleads any argument using the first "will" will not have a leg to stand on because the document is invalid, it is now only used as an illustration to give understanding to the last will.

Classic "two gospel" POV.

Paul says - there has always been only ONE Gospel Gal 1:6-9
AND that this ONE Gospel "was preached to Abraham" Gal 3:8

 

[Steve Petersen]

15 Therefore he is the mediator of a new covenant, so that those who are called may receive the promised eternal inheritance, since a death has occurred that redeems them from the transgressions committed under the first covenant. (Hebrews 9:15)​

The death in view here is, of course, the death of the mediator himself, the death of the Messiah. This passage can be a bit confusing because a covenant is different than a last will and testament. If we were reading the Greek, things would make more sense because the word diatheke, translated ‘covenant,’ can also mean a person’s ‘last will and testament.’ The Greek version of the Hebrew Scriptures, the Septuagint (LXX), consistently uses the word diatheke to translate the Hebrew word for covenant (brit). But the larger Greco-Roman society in the first century used the word diatheke to mean the last will and testament by which a person left instructions assigning the inheritance of his possessions. Paul used the same wordplay and a similar illustration in Galatians 3.

In Jewish society the rabbis had strict rules regarding the laws of inheritance. These laws are the subject of an entire tractate of the Talmud (Bava Batra.) In the Mishnaic Hebrew of the Talmud the rabbis referred to a person’s last will and testament as a deyateke, obviously a loan word from Greek, meaning exactly the same thing. The Talmud says: “Which type of document is called a deyateke? Any in which it is written, “This shall be valid and enduring upon my death.” (b. Bava Batra 135b)

16 For where a will (diatheke) is involved, the death of the one who made it must be established. 17 For a will takes effect only at death, since it is not in force as long as the one who made it is alive. 18 Therefore not even the first covenant was inaugurated without blood. (Hebrews 9:16–18)​

A covenant is not the same as a last will and testament. The blood of the first covenant was the blood of sacrifices, not the blood of the one who made the covenant, not Israel, not Moses, not the Almighty. Just as a man’s last will and testament does not go into effect until his death, so too, a covenant does not go into effect until a sacrifice has been made. The point is that simple.

 

[BobRyan]

Moses and Elijah stand with Christ in glory in Matthew 17 -- before the cross. Before the death of Christ.

"the Gospel was preached to Abraham" Gal 3:8.

They stand with Christ as "sons of the promise" -- so while the New Covenant Gospel of Jeremiah 31:31-33 is not ratified until the cross - yet its promise is claimed and reality gained even in the OT as we see in the case of Moses, Enoch and Elijah taken to heaven before the cross.