In the more than 10 years of sitting through jw meetings I don't know if I ever heard Heb 10:26-29 quoted - and although I no longer am in posession of the wtcd-rom - i do know that there are precious few references to it. What is quoted below is from a UCGI pamphlet that may be obtained in full at the address given.
"Paul and the Law" Copyright@ 2002 Church of God International - Tyler Texas PO Box 2525 75710 - for complete free copy
"The apostle describes the law as a "custodian" from which the Chirstian has been set free; yet at the same time, he views the law as holy and just and good." He affirms that only 'the doers of the law will be justified," yet declares that all who are in Christ have "died to the law.".........Little wonder Paul's epistle evokes so much controversy.....The solution lies in understanding that the law plays more than one role.
The apostle strongly denounces the idea that Christians, thru faith "over throw the law,' declaring instead that we "uphold the law." Rom 3:31..The law then is God's ethical and moral standard. It teaches us how to live.....This is the Educative role of the Law....However, the law has another function--The Judicial Role.
In it's second function, the law acts as a "custodian"-- but only for those not in Christ. it is this role of the law that Paul had in mind when he says, "You are not under law, but under grace. Rom 6:14 when he describes the law that kept us under it's power "until Christ came."
Under condemnation, the law informs us of our need for a savior--one who can block out of record of sin.....When we come to conversion, through faith in Christ, the law's role as custodian is abolished. No longer can the law demand our death...The curse has been removed. Gal 3:31
We should now be able to understand how Paul can insist upon meeting the requirement of the law while without contradiction, speaking of the law's transitory role....by calling upon the Galatians to listen to the law - the educative role - while upholding his warnings against engaging in the works of the flesh - all of which are condemned. Gal 5 .........So oviously he also recognizes the perpetual teaching nature and the judicial role of the law.
The law was added in the sense that it was given in "codified form" at Sinai. Of course this does not mean that the principles set forth in the law were previously unknown.......It is extremely important to understand that the law's abolition as custodian thru faith in Christ does not mean the abolition of the law......Paul did not say that the law died; he said we died to the law.
Serving in the "new life of the spirit", means striving no longer to break God's law. The judicial role of the law called for our death, which was fulfilled.....the educative role calls for our obedience. "I delight in the law." Rom 7:22 In Christ we are no longer under the law's power to identify and punish us as sinners....having been set free from the curse...but not the law."
WARNING - Seeking justification by the law (rather than thru faith in Christ) is not the only way to revive the law's judicial role of identifying and punishing transgressions. Returning to a life of sin--the works of the flesh--will accomplish the same.
God did give the Israelites commands concerning sacrifices--even before leaving Egypt. What he means here is that he never commanded sacrifices without moral responsibility. He is not pleased with mere sacrifices. He is not like the pagan gods."