So, on what basis does the Holy Spirit through the Apostle John assure his readers that they have eternal life? Lets take a look. In 1 John 1:6-7 John says, "If we say that we have fellowship with Him and yet walk in the darkness, we lie and do not practice the truth; but if we walk in the Light as He Himself is in the Light, we have fellowship with one another and the blood of Jesus His Son cleanses us from all sin." If you do not walk in the light, then you can have no assurance that the "blood of Jesus His Son cleanses" you from your all your sin. What does it mean to walk in the light? It is very clear from the context that walking in the light has to do with obedience to the commands of God. The question is, Do you walk in the light; Do you walk in obedience to the commands of Christ? If not, you can have no assurance that you have eternal life. We must look at this in a positive light as well. After all, John wrote this to provide his readers with assurance. If you walk in the light, if you live in obedience to the commands of Christ you can have great assurance that you have eternal life. Rejoice!
John in no way is here teaching that you must flawlessly walk in the light. NO! John is not teaching that only those who live lives of perfect obedience can have assurance that they have eternal life. This is such a big deal that John, in the very next verse, says that "if we say that we have no sin, we are deceiving ourselves, and the truth is not in us" (1 John 1:8). We also know that John is not here saying that assurance of salvation is given only to those who flawlessly walk in the light because just 4 verses after saying this he says, "And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous" (1 John 2:1).
This is such a difficult thing to communicate to people today because of a tendency to oversimplify things. Yes, we do have an advocate with the Father if we do sin, however it is true that you can have no assurance that you have eternal life if you, as a lifestyle, walk in the darkness. We all falter, we all mess up, however those who truly have eternal life, as a lifestyle, walk in the light.
So let us ask the beloved Apostle John, "JOHN! How can I know that I have eternal life?" Hear the words of the Holy Spirit through his Apostle, ""If we say that we have fellowship with Him and yet walk in the darkness, we lie and do not practice the truth; but if we walk in the Light as He Himself is in the Light, we have fellowship with one another and the blood of Jesus His Son cleanses us from all sin" (1 John 1:6-7)
Let us move on to 1 John 2:3-6, "By this we know that we have come to know Him, if we keep His commandments. The one who says, ‘I have come to know Him,’ and does not keep His commandments, is a liar, and the truth is not in him; but whoever keeps His word, in him the love of God has truly been perfected. By this we know that we are in Him: the one who says he abides in Him ought himself to walk in the same manner as He walked."
I do not know how John could have made this any clearer. "Beloved John, how can I know that I have eternal life, how can I know that I have saving faith?" Let me ask you a question, "Do you keep the commandments of God? If not, then you can have no assurance that you have eternal life, however if you do keep His commandments then rejoice for you have eternal life." Once again, John is not saying that keeping the commandments of Christ in some way merit salvation, rather he is saying that keeping the commandments of Christ is that which gives the professor of faith assurance that they have true saving faith.
Notice how emphatic John is here when he says, "The one who says, ‘I have come to know Him,’ and does not keep his commandments, is a liar." Let us imagine that John were to somehow be thrown into our present day context. Well, one day he decides to go to Starbucks to enjoy the wonderful flavors of rich espresso. He goes the counter, get his drink, and then takes his seat on one of those oh so wonderful wooden chairs with the wide seats to fit our large bottoms. After sitting for a few minutes sipping his cup of joe he notices a well dressed man come in through the door. As the man walks by the Apostle John stops him and says, "Hello friend, are you a Christian?" The well dressed man smiles at John and says, "Why yes, I am. I excepted Jesus into my heart a few years ago." John then looks at him and says, "Would you like to sit and drink coffee with me."
After ordering his drink the man comes back to the table and the two begin to talk. Their conversation starts by them telling their testimonies. After hearing about this man’s entrance into Christianity John then asks him, "Brother, so tell me how you life has changed since you have believed on the Lord Jesus." The man sort of hangs his head and says, "Well, I don’t have much time for my faith. Even though I am a follower of Christ I really haven’t changed all that much since I first accepted Christ. I mean, I know and love God and everything, but to be honest, the only real change in my life is that I have a semi-new set of beliefs and I go to church once or twice a month. I mean, I still get drunk most weekends, never read my Bible, and am not all that honest with my wife, but hey, none of us is perfect."
What would John’s response to this man be? Well, look at what he says in this verse. I suspect that John would say, "What, you know and love God? No you don’t, you are a liar, because the evidence that you know God is that you keep His commandments." John actually calls the one who claims to know God and yet does not keep His commandments a liar. Once again, John here speaking of a life style of disobedience to the commands of Christ. The one who sincerely struggles in their battle with sin need not go away thinking themselves damned to hell.
However, the one who is using the reality that they are imperfect and the reality of a graced based salvation as a crutch they use to justify their sin ought to be concerned for their soul. The one who, as a lifestyle, lives in disobedience to the commands of Christ ought to be concerned for their soul.
More on this later.