I’m not exactly sure what you mean by saying, “IF a person sins.” If you mean, “If a person sins AT SOME POINT in their life,” the Bible is clear and emphatic that EVERY PERSON SINS. Romans 3:23 declares, “For ALL HAVE SINNED and fall short of the glory of God” (NKJV). But perhaps you mean, “If a person sins JUST BEFORE he/she dies.” If that is the scenario you are presenting then you may also be thinking, “If a person sins just before he/she dies without confessing that sin.” Either way, my answer to your question is going to be the same, for the real issue isn’t THEIR SIN, but whether or not THEIR SINS HAVE BEEN FORGIVEN. The answer to that question will determine what happens to them when they die. Before we see what happens to one who has had their sins forgiven and what happens to those whose sins have not been forgiven, let’s see HOW one is forgiven of all of their sins.

In Acts 10:43 the Apostle Peter preached, “Of Him (Jesus Christ) all the prophets bear witness that through His name everyone who believes in Him receives forgiveness of sins” (NASB). Forgiveness of sins is THROUGH JESUS CHRIST! There is no other way to be forgiven. The Apostle Paul preached the exact same message, “Therefore let it be known to you, brethren, that through this Man is preached to you the forgiveness of sins; and by Him everyone who believes is justified from all things from which you could not be justified by the Law of Moses” (Acts 13:38-39). Again, forgiveness of sins is THROUGH JESUS CHRIST! How can we be forgiven through Jesus Christ? Ah, because “Jesus died for our sins!” We saw that the prophets bore witness to this. Let’s read what the prophet Isaiah said about this. “But He (Jesus Christ) was wounded for our transgressions; He was bruised for our iniquities, the chastisement for our peace was upon Him, and by His stripes we are healed. All we like sheep have gone astray, we have turned, everyone, to his own way; and the LORD has laid on Him the iniquity of us all” (Isaiah 53:5-6). Hundreds of years before Jesus was born Isaiah prophesied that Jesus would take our place in death and judgment on the cross FOR OUR SINS. We deserved to die and to be judged of God, but in love the Son of God became a Man so He could be our Divine Substitute. The moment one believes in Him as their Sin-bearer, as the One who paid the price for our sins that a holy God demanded, they receive the complete forgiveness of sins. Some ask, “But how many of our sins did Jesus die for? Was it just for the sins we committed up until the time we believe on Him?” I usually respond by asking them this question, “How many of our sins were future when Jesus died?” Most will say (and rightly so), “Why, all of my sins were future when He died, for that was almost 2,000 years ago.” Yes, ALL OF OUR SINS were “laid on Jesus,” and thus the believer has forgiveness of every sin they’ve ever committed or will commit.

Now we can answer your question. When a BELIEVER dies their spirit goes immediately to heaven. The Lord Jesus told the penitent thief who had believed on Him, “Assuredly, I say to you, today you will be with Me in Paradise” (Luke 23:46). Think of it, that man woke up that day a no-good thief, yet he closed his eyes in death and opened them up in heaven. He had heard the Lord say earlier, “Father, forgive them, for they know not what they do” (verse 34) and he believed he was forgiven through Jesus Christ! I would also encourage you to read and meditate on 2nd Corinthians 5:1-8 and Philippians 1:20-23 to see that the believer goes to be with Christ in heaven the moment they die.

When the UNBELIEVER dies their spirit goes to a place of torment where they will await the final judgment where they will be cast into the lake of fire. You can read about this in Luke 16:19-23 and Revelation 20:11-15. They could have been forgiveness through Jesus Christ, but they refused to believe on Him. How solemn are the words of Jesus to all who reject His forgiveness through unbelief, “Therefore I said to you that you will DIE IN YOUR SINS; for if you do not believe that I am He, you will DIE IN YOUR SINS” (John 8:24).  (374.1)  (DO)