The meaning of this is clear. In the old covenant the stress was laid on the outward rite; but in the new covenant, for burnt-offerings and sacrifices for sin are substituted first the entire devotion and consecration of the blessed Lord to His Father's will; and next, ours in Him.
It is very noticeable that by the offering of the cross, in which the Saviour's yielded will culminated, we are said to have been sanctified, consecrated, or set apart once for all (Heb 10:10). The thought there is, evidently, that our Saviour's death has implicated us forevermore; and that His Church, whom He represented in that supreme act, is forever pledged to be dead unto the world and sin.
But still later we learn that He hath perfected forever them that are sanctified (Heb 10:14). The change of tense surely indicates that what was accomplished for us in the purpose of God when Jesus died, must be accomplished in us by the operation of the Holy Spirit. Every time, therefore, our will is brought into more perfect union with that of God, a further step is taken toward that glorious elevation which Jesus made ours in the death of the cross.
And if you would have an incentive to this, remember how Jesus promised that all who would do the will of God should be reckoned members of the holy family (Mat 12:46-50). Are you a member of that family? You may be, and sit only on the outer circle, for the constituent members are always altering their position toward the central Christ; now advancing toward the inner heart, now receding. Oh, see to it that you are not only within the holy circle of the will of God, but that you are near the golden centre where Jesus is seated.