The Bible says that God is “holy, holy, holy” (Isaiah 6:3), that He is a righteous God (Psalm 11:7), and that, because of this, He can have nothing to do with sin (Psalm 5:4). He hates sin and must punish all sinners for their sin committed against Him (Ezekiel 18:20; Romans 1:32; Psalm 5:5). Scripture also says that all humans have sinned against God (Romans 1-3; 3:23) and broken all His commandments (James 2:10). Because of this, we have been separated from God (Isaiah 59: 2) and have become His enemies (Romans 8:7; James 4:4). Therefore–because we are sinful and He is holy–all humanity is condemned to hell–“to suffer the punishment of eternal destruction, away from the presence of the Lord and from the glory of His might" (2 Thessalonians 1:5-10).
People believe that they will be saved by having their good works outweigh the bad ones, but Paul says in Romans 2:5 that this is actually a storing "up [of] wrath for yourself in the day of wrath and revelation of the righteous judgment of God." This is because the purpose of the law was never that we would attain salvation through it, but that by it we would come to an understanding of sin and our condemnation before a holy God (Romans 3: 19-20). For "by the works of the Law no flesh will be justified in His sight; for through the Law comes the knowledge of sin" (v. 20).
So, how then can we be saved from God's eternal judgement? God has provided the means for our salvation. For "God so loved the world that He sent His only Son, (Jesus Christ, who is God in the flesh [John 1; Hebrews 1; Colossians 1; Revelation 1; etc.]) that whoever believes in Him might not perish but have everlasting life" (John 3:16). "For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord" (Romans 6:23). Jesus became the sacrifice for the sins of the world in whom the wrath of God against sinners was appeased through Him taking our place (1 John 2:2; Romans 3:25). Jesus died on the cross and drank the cup of the wrath of God that was appointed to us (Psalm 75:8, Romans 5:9). Every sinful deed, word, and thought (past, present, and future) of God’s elect were imputed to Him on the cross so that through this "great exchange," Jesus’ righteousness could be imputed to His elect when they believe in Him (Romans 4:1-8). Since the standard of heaven is God Himself (Matthew 5:48; Leviticus 19:2), this was the only way to redeem humanity. God's holiness demands that justice be met on our behalf. Jesus paid our debt by dying on the cross so that we could be reconciled to God (2 Corinthians 5:21). God will not only never save a sinner because of his "good works," but He will also never save a sinner who simply asks Him for forgiveness for his sins. There must be a perfect Substitute–a perfect sacrifice in whom the justice of God is appeased. This was Jesus Christ, the holy Son of God.
"Surely our griefs He Himself bore, and our sorrows He carried ... He was pierced through for our transgressions, He was crushed for our iniquities; the chastening for our well-being fell upon Him, and by His scourging we are healed. All of us like sheep have gone astray, each of us has turned to his own way; but the Lord has caused the iniquity of us all to fall on Him.… And as for His generation, who considered that He was cut off out of the land of the living for the transgression of my people, to whom the stroke was due? … But the Lord was pleased to crush Him, putting Him to grief; if He would render Himself as a guilt offering” (Isaiah 53:6-10).
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Three days later, Jesus rose from the dead (Luke 24:6-7), fulfilling Old Testament prophesy (Job 19:25–27; Psalm 49:15; 73:23–28; Isaiah 25:8; 26:19; etc.), and showing that the Father had accepted His sacrifice (Acts 17:31). Then, He ascended into heaven and sat at the right hand of the Father (Luke 22:69; Romans 8:34). We now await for His second coming (Philippians 3:20), when He will gather His elect to Himself (1 Thessalonians 4:17), pour out His judgment upon all the wicked of the earth (Revelation 7-18; Psalm 2, Zechariah 14), and plant His millennial kingdom where He will bodily reign over the whole earth from Jerusalem (Revelation 20:1-6; Jeremiah 3:17).
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