Have you ever wondered why Jesus had to die on a cross for people's sins? After all, if God is loving, why couldn’t he just forgive everyone instead of putting his Son through all that suffering to make atonement for sin?
We find the answer to this question in God’s attribute of simplicity. A lot of people view simplicity as meaning “uncomplicated,” something that is easy to do. True, the word is certainly used that way. When referring to God as being simple, however, we mean that God is not complex. God is pure spirit; he is not made up of a bunch of parts (John 4:24).
Let’s use an everyday cooking example to make this point. When making stew, people usually use a variety of ingredients, including meat, potatoes, grains, vegetables, broth, and various spices, to name a few. All these ingredients are combined together to make a nourishing meal. Many people view God in a similar way. They look at all of God’s attributes—including his love, holiness, goodness, righteousness, mercy, justice, and greatness—and think that all these things are combined together in the being of God.
Because he is spirit, God is always purely all of his attributes in complete perfection and unity. It is impossible for God to allow, say, his mercy to override his justice. His holiness never conflicts with his love. God must be true to all his attributes, because to do otherwise would be to deny his own self. As theologian Michael Horton so aptly states in his book The Christian Faith, “God would not be God if he did not possess all his attributes in the simplicity and perfection of his essence.”
It is because of God’s simplicity that he sent his Son to die on a cross for our sins. In this world we cry out against injustice. We are outraged over incidences where people hurt others and don't bear the consequences of their wrongdoing. How much more is this the case when God sees his righteous law violated? He cannot look the other way. In order to uphold his attributes of holiness, righteousness, and justice, God must judge and punish sin (Num. 14:18; Nah. 1:3).
God became the solution to the problem of sin. Since there was no way for sinful humans to keep God’s law perfectly or completely atone for their sins, Jesus was born in the flesh so he could fulfill the whole law and be the perfect sacrifice on behalf of all who put their faith in him:
And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God, waiting from that time until his enemies should be made a footstool for his feet. For by a single offering he has perfected for all time those who are being sanctified. (Heb. 10:11–14)
At Golgotha, we see the God who is both “just and the justifier” (Matt. 27:33–35; Rom. 3:26). Horton points out that it is at the cross where “we see how far God is willing to go in order to uphold all of his attributes in the simplicity of his being.” It was entirely fitting that such a loving God did not spare even his own Son but rather delivered him up for his sin-laden image bearers so that we could be restored to fellowship with him (Rom. 8:32; 2 Cor. 5:19). Jesus was not forced to make this sacrifice either. He told his disciples that no one could take his life away, but he laid it down of his own accord because of his unfathomable love for his sheep (John 10:18; 15:13).
Take a moment and think about the attributes of God we see on display at the cross, and marvel at what a good, holy, loving, just, and merciful God we have! Rest today in the knowledge that, because our God is simple, we can trust him to uphold all his glorious attributes. The greatest proof of this is the finished reconciling work of Christ, which is counted to all who trust in him alone for salvation.