The Law was merely a shadow because it was incapable of showing God’s perfection. According to George Guthrie, “That it constitutes a ‘shadow’ suggests that the earthly system mimics enough of the original to point God’s people to greater heavenly realities. Nevertheless, by its perpetual need for new sacrifices, it demonstrates its inadequacy.”
When the author of Hebrews speaks of the good things to come, he was speaking in regards to Christ coming, he was just referencing the Law and something better was coming.
Just as almost everything else the author has been saying the OT sacrifices of animals was ultimately pointing believers to the ultimate sacrifice that would be made by Jesus Christ himself once for all. These animal sacrifices would be made for the purification, but they were unable to remove sins. Guthrie informs us that, “In Hebrews 10:4, as in the Romans passage, the idea of ‘removing’ sin speaks of the burden sin placed on the worshipers conscience being lifted in a decisive, perpetually effective cleansing, which establishes one’s status before God. These animal sacrifices had to be made daily all day long for the people whether it was a pair of doves, or bulls and goats. The sacrifice Christ made was a one-time deal; his death far surpasses that of any other creature.
Guthrie list four comparisons between the Levitical priesthood and Christ high-priest status. 1) Under the law sacrifices were offered daily; In Christ it was offered once for all time. 2) The priest stood when offering the sacrifice; Jesus sat down after his work was completed. 3) Under the law multiple sacrifices were offered again and again; in Christ one sacrifice. 4) no matter how many times sacrifices were offered they never could takeaway sins; Christ accomplished perfection of those whom the sacrifice was offered.Hebrews 10:14 refers to the elect those who would call upon the name of the Lord to be saved. The word speaks of new covenant people as having been made whole or complete. By Jesus being the ultimate sacrifice we should not willing sin so easily. While the nation of Israel has its customs of sacrifice it costs them something, to whereas all we are asked for is obedience to the Gospel. Even if we have never been Jews our new life that has been bought and paid for in the death of Jesus should hold more appeal to us and keep us from longing for our old way of life.