Summary: There are four major biblical reasons why the atonement was necessary
There are four major biblical reasons why the atonement was necessary, most of which are intimately connected with God’s nature or character.
1. God’s Righteousness and Justice
Many people who object to the biblical doctrine of the atonement do so because they do not understand who God is. They reason within themselves: “Why doesn’t God simply forgive and forget? Wouldn’t God forgive people as long as they say they are sorry and endeavor to be a better person? Isn’t a little vow of
acceptance of God all that is necessary? Isn’t the idea that only the death and shed blood of Christ can remove sin extreme and fanatical?” The reason God cannot simply let sin slide or sweep it under the rug and pretend it doesn’t exist is because He is righteous and just. “The LORD is righteous, He is in her midst, He will do no unrighteousness” (Zeph.3:5). “Righteousness and justice are the foundation of Your throne” (Ps. 89:14). “He is the Rock, His work is perfect; for all His ways are justice, a God of truth and without injustice; righteous and upright is He”(Dt. 32:4). Therefore, Abraham, who knew God’s character, could ask Jehovah: “Shall not the Judge of all the earth
do right?” (Gen. 18:25). Likewise, the apostle Paul could say, “Is there unrighteousness with God? Certainly not!” (Rom. 9:14). God can only do what is
right. Because of His nature, He can only do what is just.
God’s nature demands that sin be punished. If God refused to give sin its full measure of punishment then He could not claim to be perfectly just. God’s
infinite holiness, justice and righteousness of necessity demand the infliction of punishment on the sinner himself or on an appropriate substitute. The Bible contains many passages that declare that God has to punish sin. Jehovah said, “I will not justify [i.e. declare righteous] the wicked” (Ex. 23:7). “We are told repeatedly that He will by no means clear the guilty, Ex. 34:7; Num. 14:18; Nah. 1:3. He hates sin with a divine hatred; His whole being reacts against it, Ps. 5:4-6; Nah. 1:2; Rom. 1:18. This aspect is why the word "repentance" is a necessity in the plan of salvation.
2. God is Holy
Another aspect of God’s character that necessitates the atonement is His holiness. “The nature of God is perfect and complete holiness. This is not an optional or arbitrary matter; it is the way God is by nature. He has always been absolutely holy. Being contrary to God’s nature, sin is repulsive to Him.
He cannot look upon it. He is compelled to turn away from it.” God’s infinite holiness causes Him to hate sin with a perfect hatred. God is so holy that before sinful men can come into His presence and have fellowship with Him the guilt of their sin must be removed and they must be clothed with perfect righteousness.
The attribute of God that is emphasized by Scripture above all other attributes (including love) is His holiness. “Who is like You, O LORD among the gods? Who is like You, glorious in holiness” (Ex. 15:11). Jehovah is so holy that the mighty seraphim continually cry out before Him, “Holy, holy, holy is the LORD of hosts; the whole earth is full of His glory” (Isa. 6:3; Rev. 4:8).