If there is only one point or theological truth you must understand about the cross, it’s the substitutionary atonement of Christ. It’s easy to get caught up thinking the extent of the atonement is the major player at the table, after all, it’s the L in TULIP . . . there is no S. But we fail in our worship if we neglect to understand what exactly happened on the cross and why it’s important for us. God devotes much attention to developing and instructing us regarding the nature of His son’s sacrifice. His work is the foundation for our worship, both individually and corporately. There are some who reject this doctrine calling it divine murder.
It’s easy to get involved in these discussions and debate those who put forth alternative positions. Sometimes I hear people say, “We should know error so we can deal with it.” When I was a bank teller, there were thousands of frauds and fake bills on the market. They showed us two different fake bills. Why? Because when you know the truth and have convictions regarding the truth, you’ll spot the fake instantly. This is true. Every fake bill that crossed my desk I found. Not because I had encountered the false doctrine before, but rather due to knowing the true ones so well. We need to know and have convictions regarding the Gospel, specifically the most important detail regarding the cross. I pray the following aids us in our worship of Him by drawing us to the significance of the cross.
Why do we need a sacrifice for our sins?
The Law requires a sacrifice for our sins. Why? Because our sins are worthy of death. We are under the death penalty. God says that penalty can be removed by the death of a sacrifice on our behalf. Instead of me dying, the sacrifice dies in my place. OT worshipers offered sacrifices for their transgressions. When a person transgressed the Law, repentance and forgiveness were required. So the transgressor brought a sacrifice to the altar for atonement. Yet OT sacrifices were insufficient because they only covered sin and could not remove sin. Hebrews explains, “Accordingly both gifts and sacrifices are offered which cannot make the worshiper perfect in conscience, since they relate only to food and drink and various regulations for the body until a time of reformation” (9:9-10). The sacrifices under the OT Law cannot make people perfect. In fact, the Law does not exist to make anyone perfect.  The Law trains us for the need for a greater sacrifice that can do away with sin.
Without the Law, we would have nothing instructing us of the need for blood to be shed for the forgiveness of sin, “According to the Law . . . all things are cleansed with blood, and without the shedding of blood there is no forgiveness” (Heb 9:22). But the only thing witnessed under the law is goats, birds, and cows. How can those deal with our sin? They can’t. So the Law sets up and prepares us to look for a better sacrifice. Jesus is the better sacrifice needed to deal with our sin nature — He fulfills the Law (Matt. 5:17-19).
The Law establishes the need for a blameless sacrifice to be offered on behalf of the sinner. Christ is the greatest sacrifice ever offered, the only one ever needed, because He offered up “His body without blemish to God” (Heb 9:14; see also Heb 7:26-28). Read the Gospels and compare His life to the Law. No deceit, sin, or broken law will be found in Christ. He is the only person to live perfectly holy. He is therefore the perfect sacrifice.
We think of Christ on the cross, numbered among the transgressors. This is 100% true and fulfills Isaiah 53. But it’s also true to think of Christ, the Son, on the altar of God in heaven as the blameless lamb. “For Christ did not enter a holy place made with hands, a mere copy of the true one, but into heaven itself, now to appear in the presence of God for us” (Hebrews 9:24).
“For” This small, almost glossed over preposition is a big deal. The Greek original is ὑπὲρ (huper), meaning “on behalf of” or “for the sake of someone.” The most authoritative Greek lexicon, BDAG, defines it, “a marker indicating that an activity or event is in some entity’s interest.” This one simple preposition allows us to interpret the sentence “. . . to appear in the presence of God on our behalf.” This is precisely the idea conveyed in OT sacrifices, “The priest enters [Holy of Holies] once a year [Day of Atonement], not without taking blood, which he offers huper himself and the sins of the people committed in ignorance” (Heb 9:7). God always views sacrifices on behalf of the sinner. We use substitutionary atonement to describe this truth.
What result does Christ sacrifice provide? Hebrews 9 -10 provides some answers.
- The cross initiates the New Covenant (Heb 9:15-20). Now believers live with the indwelling Holy Spirit. We have forgiveness from our sin nature. The law is placed in our heart. There is some question as to what this means. The law shows us sin and tells us how to be reconciled to God. I’d advocate the indwelling law is best communicated as a function of the Holy Spirit who now convicts us of our sinfulness.
- Christ’s atonement removes the sin nature providing a new nature. “We have been set a part through the offering of the body of Jesus Christ once for all. . . . For by one offering He has perfected for all time those who are sanctified (set a part)” (Heb 10:10 & 14). OT sacrifices could only cover and grant temporary forgiveness. Christ’s sacrifice perfectly cleanses the believer changing our nature. It sets us a part and makes us holy.
- Coupled with this is the forgiveness of sins. Because of Christ’s sacrifice, believers are forgiven. Meaning God chooses to no longer charge our sins against us and He does not bring them back up against us. My past, present, and future sins have been dealt with and God will not hold them against me.
- I can now come into the Triune God’s presence. The veil existed in the Temple to communicate to worshipers access to God is not possible. Now, the veil is torn and we have access to the Triune Lord. Because of Christ, we enter into God’s presence eternally. This is the priesthood of believers.
- We can and should remind ourself, “Christ died in my place. I deserved to die. He did not. He died in my place on my behalf.”
Substitutionary atonement is a big deal. God makes a big deal about. If there were one truth about the cross we should know best, I’d advocate knowing substitutionary atonement. The OT sets it up and teaches us how God resolves, justifies, and forgives sinners. The NT reveals Christ’s work as the lamb of God. It’s such a big deal God calls us to proclaim it in our churches and unify around it through communion.
Is the atonement important for the church? Jesus commissions Communion (or the Lord’s Supper) to the church to be practiced habitually for the purpose of unifying the church. Not only does His death bring me to Him and unite me to Him, it unites the church reminding us of His sacrifice and the results from His death (1 Cor 10:16-17). “For as often as you eat this bread and drink the cup, you proclaim the Lord’s death until He comes” (1 Cor. 11:26). Paul tells us, “This is my body, which is huper you; do this in remembrance of Me” (1 Cor. 11:24). We proclaim the substitutionary death of Christ. Communion draws us to the benefits of that death, “This cup is the new covenant in My blood; do this, as often as you drink it, in remembrance of Me” (1 Cor 11:25). The substitutionary atonement should be remembered because God uses this truth to unify His people. It’s hard to be disjointed and factitious with others when we have to be reconciled with each other to partake of communion. It’s even harder to be prideful and factitious when we realize who we are because of His death on our behalf.
How should I respond to His death? It should lead me to praise Him, be thankful, and serve others. Struggling with thanksgiving? Think on the cross. Contemplating the cross and Christ’s atonement should not be merely for intellectual gain and blog wars.  The reality of His sacrifice should encourage our worship. Hebrews, “Let us continually offer up a sacrifice of praise to God, that is, the fruit of lips that give thanks to His name. And do not neglect doing good and sharing, for with such sacrifices God is pleased” (13:15-16). In verses 11-14 the author reminds us of Christ’s atonement, rejection, and sacrifice. In 15-16 he tells us how we should respond. We did nothing to deserve this death. We are not worthy of His death. He, worthy of nothing but praise and glory, suffered and died for those who are worthy of death. Consider the chorus to this song. It is the appropriate response to His work.
“Your blood, has washed away my sin, Jesus thank you. The Father’s wrath, completely satisfied, Jesus thank you. Once your enemy, now seated at your table, Jesus thank you.”
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 I’d probably encourage you, before you fight with someone over the L / extent of the atonement, find out if he/she holds to substitutionary atonement. If we don’t get the S, then the extent is a worthless conversation. 🙂