John was consistent with the Father and Jesus
John clarifies that keeping God’s word is the same as keeping his commandments.
“And by this we know that we have come to know him, if we keep his commandments. Whoever says “I know him” but does not keep his commandments is a liar, and the truth is not in him, but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him: whoever says he abides in him ought to walk in the same way in which he walked. Beloved, I am writing you no new commandment, but an old commandment that you had from the beginning. The old commandment is the word that you have heard.” (1 John 2:3-7)
“Let what you heard from the beginning abide in you. If what you heard from the beginning abides in you, then you too will abide in the Son and in the Father.” (1 John 2:24)
“If you know that he is righteous, you may be sure that everyone who practices righteousness has been born of him.” (1 John 2:29)
John defines sin this way: “sin is lawlessness”. Sin (lawlessness) is further described as “of the devil” and “not of God”. The opposite of sin (lawlessness) is righteousness.
“Everyone who makes a practice of sinning also practices lawlessness; sin is lawlessness. You know that he appeared to take away sins, and in him there is no sin. No one who abides in him keeps on sinning; no one who keeps on sinning has either seen him or known him. Little children, let no one deceive you. Whoever practices righteousness is righteous, as he is righteous. Whoever makes a practice of sinning is of the devil, for the devil has been sinning from the beginning. The reason the Son of God appeared was to destroy the works of the devil. No one born of God makes a practice of sinning, for God’s seed abides in him, and he cannot keep on sinning because he has been born of God. By this it is evident who are the children of God, and who are the children of the devil: whoever does not practice righteousness is not of God, nor is the one who does not love his brother.” (1 John 3:4-10)
The next passage says believing in the name of Jesus is a commandment along with loving one another. (See also Deuteronomy 18:15-19 and Revelation 14:12.)
“Beloved, if our heart does not condemn us, we have confidence before God; and whatever we ask we receive from him, because we keep his commandments and do what pleases him. And this is his commandment, that we believe in the name of his Son Jesus Christ and love one another, just as he has commanded us. Whoever keeps his commandments abides in God, and God in him. And by this we know that he abides in us, by the Spirit whom he has given us.” (1 John 3:21-24)
John quotes the law as authoritative and to be obeyed.
“And this commandment we have from him: whoever loves God must also love his brother.” (1 John 4:21)
“By this we know that we love the children of God, when we love God and obey his commandments. For this is the love of God, that we keep his commandments. And his commandments are not burdensome.” (1 John 5:2-3)
John considered obeying commands of the Father to be “walking in the truth”.
“I rejoiced greatly to find some of your children walking in the truth, just as we were commanded by the Father.” (2 John 1:4)
Once again John quotes the law “we have had from the beginning” and references a command from Leviticus 19:9-18.
“I rejoiced greatly to find some of your children walking in the truth, just as we were commanded by the Father. And now I ask you, dear lady—not as though I were writing you a new commandment, but the one we have had from the beginning—that we love one another. And this is love, that we walk according to his commandments; this is the commandment, just as you have heard from the beginning, so that you should walk in it.” (2 John 1:4-6)
John takes a strong position on abiding in the teaching of Christ (who taught to obey God’s law).
“Everyone who goes on ahead and does not abide in the teaching of Christ, does not have God. Whoever abides in the teaching has both the Father and the Son. If anyone comes to you and does not bring this teaching, do not receive him into your house or give him any greeting, for whoever greets him takes part in his wicked works.” (2 John 1:9-11)
In Revelation, John says those who keep the commandments of God hold to the testimony of Jesus and are known as the saints.
“Then the dragon became furious with the woman and went off to make war on the rest of her offspring, on those who keep the commandments of God and hold to the testimony of Jesus. And he stood on the sand of the sea.” (Revelation 12:17)
“Here is a call for the endurance of the saints, those who keep the commandments of God and their faith in Jesus.” (Revelation 14:12)