Substitutionary atonement which is not to be confused with the Protestant belief in penal substitutionary atonement (PSA).
SDA theologian Norman R. Gulley explains what the SDA Church means by the term “substitutionary” in a 1990 Journal of the Adventist Theological Society article titled, Toward Understand the Atonement, where he writes:
“Rightly used, the word “substitutionary” in no way connotes that Christ took our place in living a perfect life so that we do not need to be fitted for heaven! It need not connote this anymore than it connotes that He ascended to heaven in our place. The word “substitutionary,” properly employed, applies solely to Christ’s taking our place at the cross, doing for us what we could never do for ourselves, that is, perish in the second death (Revelation 20:6) and still live for eternity. In paying the price for our sins He alone could be our substitute. This is the most glorious good news—the wondrous exchange.”
Norman R. Gulley Toward Understanding the Atonement (1990), Journal of the Adventist Theological Society, pg. 68
When the SDA Church uses the word atonement, they actually refer to their novel doctrine of the investigative judgment and the heavenly sanctuary. As can be seen in Salvation: Contours of Adventist Soteriology, a scholastic work by SDA scholarship, Jon Paulien explains:
One of the most debated topics of Christian theology is expressed in these questions: Why the cross? What really happened at the cross? The answers to these questions have been widely debated under the general heading of the atonement. But when Seventh-Day Adventists (SDA) approach the matter of atonement, an immediate dilemma is perceived. When Adventists talk about atonement, they refer specifically to what Jesus is doing now in the heavenly sanctuary. On the other hand, when scholars outside the Seventh-Day Adventist Church discuss the atonement, they refer specifically to the cross of Jesus Christ and what God was doing there.
JON PAULIEN, SALVATION: CONTOURS OF ADVENTIST SOTERIOLOGY, CHAPTER 10, PG. 189
Foundational the SDA system of theology is their Great Controversy Worldview which informs what the SDA Church teaches about who Jesus is, why He came, why He had to die, etc. And it’s this extra biblical paradigm that is brought to the biblical text to be the interpretive lens. In this model, Jesus came—in part—to silence accusations made by Satan prior to the creation of the earth. Part of this accusation was that God’s law, the 10 Commandments, were not fair and needed changed.
This eventually led to war breaking out in Heaven, Satan being banished, and God the Father and the Son creating the earth along with mankind as a testing event to vindicate God’s character from these accusations of Satan before the watching universe. When man fell, Jesus proposed a plan to His Father that was accepted which entailed Jesus coming to pay the penalty for sin which is death and live as the great Example by keeping the law perfectly. This demonstration silenced Satan’s accusations and showed man that he, too, can keep the law and silence Satan with Jesus’s help which will ultimately vindicate God in the great controversy.
It is this backdrop that Mr. Gulley has in mind when he says that Jesus did not come so that we don’t need to be “fitted for heaven”—a phrase used within SDA theology for sinless perfectionism and perfect law keeping. Because in SDA theology, the atonement is about Jesus enabling you to be able to keep the law perfectly, vindicate God against Satan, and prove that you are safe to save.