Hebrews 10:5-10

⁵ Therefore, when He came into the world, He said: “Sacrifice and offering You did not desire, But a body You have prepared for Me. ⁶ In burnt offerings and sacrifices for sin You had no pleasure. ⁷ Then I said, ‘Behold, I have come— In the volume of the book it is written of Me— To do Your will, O God.’ ” ⁸ Previously saying, “Sacrifice and offering, burnt offerings, and offerings for sin You did not desire, nor had pleasure in them” (which are offered according to the law), ⁹ then He said, “Behold, I have come to do Your will, O God.” He takes away the first that He may establish the second. ¹⁰ By that will we have been sanctified through the offering of the body of Jesus Christ once for all.

Commentary

Vs. 5-7 ⁵ Therefore, when He came into the world, He said: “Sacrifice and offering You did not desire, But a body You have prepared for Me. ⁶ In burnt offerings and sacrifices for sin You had no pleasure. ⁷ Then I said, ‘Behold, I have come— In the volume of the book it is written of Me— To do Your will, O God.’ ” 

Now it is because of the insufficiency of those animal sacrifices that God the Father did not require the Lord Jesus Christ His Son to offer any of those. Instead as Psalm 40:6-8 declares, God prepared a body, a fully human body for His Son Jesus to be brought into the world. And thus not only to grow up and to live in, but also to die for us all, which He did by His own death on the Cross (John 3:16). 

Vs. 8-9 ⁸ Previously saying, “Sacrifice and offering, burnt offerings, and offerings for sin You did not desire, nor had pleasure in them” (which are offered according to the law), ⁹ then He said, “Behold, I have come to do Your will, O God.” He takes away the first that He may establish the second. 

God's pleasure was not in the sacrificial offerings that the Israelite's offered according to the Law. God's pleasure is in the reconciling of His people and all people equally who believe and obey Him through His Son the Lord Jesus Christ. Therefore the ordinances of the first Covenant, the Old Covenant have been removed by the will of God so that He may establish the second, the New Covenant ushered in by the Everlasting Atonement He has provided for us all through His Son. Therefore God has taken away the first so that He may establish the second. The New Covenant then is the only Covenant that is in effect and enforce for everyone who believes in the Lord Jesus Christ (Rom 6:14). 

Vs. 10 "By that will we have been sanctified through the offering of the body of Jesus Christ once for all."

Therefore it is by God's Will, that we have been sanctified (gr. ἁγιάζω, Str. 36; LN. 88.26) through the offering of the body of Jesus Christ once and for all. Now sanctified here means we have been made holy, that is set apart in the sight of God by the Sacrifice of the Lord Jesus Christ by His Spirit indwelling and sanctifying ours (consider 1 Cor 1:2; 6:11 etc.). 

Scripture Quotations
The New King James Version. Nashville: Thomas Nelson, 1982.

Additional Resources Consulted 

Kittel, Gerhard, Gerhard Friedrich, and Geoffrey William Bromiley. Theological Dictionary of the New Testament. Grand Rapids, MI: W.B. Eerdmans, 1985.

Louw, J. P., & Nida, E. A. (1996). Greek-English lexicon of the New Testament: based on semantic domains (electronic ed. of the 2nd edition., Vol. 1, p. 744). New York: United Bible Societies.