Summary: The "litmus test" of our knowledge of Christ is obedience to His commands.
By This We Know
Turn with me to 1 John, chapter 2 - this will be our primary text this morning. Beginning with verse 3, “We know that we have come to know Him if we obey His commands. The man who says I know Him but does not do what He commands is a liar and the truth is not in him. But if anyone obeys His word, God’s love is truly made complete in Him. This is how we know we are in Him. Whoever claims to live in Him must walk as Jesus did.”
You know, in the news today we hear a lot about litmus tests, don’t we? We hear it a lot in politics in this election year especially, in reference to the appointment of judges and whether or not a judge’s position on abortion is going to pass the litmus test, or whether it should be a litmus test at all for his/her appointment. Some of you may remember from science or chemistry class that litmus is a coloring matter. It’s obtained from lichens, moss-like plants, and a litmus test is a scientific test. Acids turn blue litmus red, and bases turn red litmus blue. It’s a simple and sure test to distinguish one from the other. Here in this passage, God gives us a litmus test regarding our relationship with Him, how we can know that we know Him.
The title of this morning’s message is By This We Know. That’s a phrase that’s used in several different ways throughout the book of 1 John. In the passage we just read, in 1 John 2:3 (quickview)  it says we know that we have come to know Him if we obey His commands. Later in the same chapter, 2:29 it says that if you know He is righteous you know that everyone who does what is right has been born of Him. In 1 John 3 (quickview) : 18-19 it says, “Dear children, let us not love with words or tongue but with actions and in truth.” This, then, is how we know that we belong to the truth and how we set our hearts at rest in His presence. In chapter 3:24 it says “those who obey His commands live in Him and He in them. And this is how we know that He lives in us. We know it by the spirit He gave us.” In 1 John 5:2-4 (quickview) , there again, “this is how we know that we love the children of God, by loving God and carrying out His commands. This is love for God, to obey His commands. And His commands are not burdensome, for everyone born of God overcomes the world. This is the victory that has overcome the world, even our faith.”
The common denominator in each of these passages is - obedience. We see the phrases “everyone who does what is right” … we see love with actions and in truth, we see those who obey His commands, we see the phrase “carrying out His commands.” The common denominator is obedience. Obedience is a great theme throughout scriptures, from the Old Testament all the way through the New Testament. I think, however, we often think of obedience as primarily an emphasis that’s in the O.T. We don’t really think of it as a N.T. theme. I think the reason for that is because we want to be so careful to remember that we can’t earn salvation by what we do that we tend to throw the baby out with the bath water.