10:6 In burnt offerings. Quoted from Ps 40:6. Burnt offerings were wholly consumed. See Le 1:17.
And [sacrifices] for sin. See Le 4:1-5:13. They were so called because of their special reference to sin.
Thou hast no pleasure. In neither burnt offerings nor sacrifices had God pleasure; that is, they did not fully meet his will.
10:1-10 The apostle having shown that the tabernacle, and ordinances of the covenant of Sinai, were only emblems and types of the gospel, concludes that the sacrifices the high priests offered continually, could not make the worshippers perfect, with respect to pardon, and the purifying of their consciences. But when God manifested in the flesh, became the sacrifice, and his death upon the accursed tree the ransom, then the Sufferer being of infinite worth, his free-will sufferings were of infinite value. The atoning sacrifice must be one capable of consenting, and must of his own will place himself in the sinner's stead: Christ did so. The fountain of all that Christ has done for his people, is the sovereign will and grace of God. The righteousness brought in, and the sacrifice once offered by Christ, are of eternal power, and his salvation shall never be done away. They are of power to make all the comers thereunto perfect; they derive from the atoning blood, strength and motives for obedience, and inward comfort.