The reading is from St. John's First Universal Letter 2:18-29; 3:1-8

Brethren, it is the last hour; and as you have heard that antichrist is coming, so now many antichrists have come; therefore we know that it is the last hour. They went out from us, but they were not of us; for if they had been of us, they would have continued with us; but they went out, that it might be plain that they all are not of us. But you have been anointed by the Holy One, and you all know that I write to you, not because you do not know the truth, but because you know it, and know that no lie is of the truth. Who is the liar but he who denies that Jesus is the Christ? This is the antichrist, he who denies the Father and the Son. No one who denies the Son has the Father. He who confesses the Son has the Father also. Let what you heard from the beginning abide in you. If what you heard from the beginning abides in you, then you will abide in the Son and in the Father. And this is what he has promised us, eternal life.

I write this to you about those who would deceive you; but the anointing which you received from him abides in you, and you have no need that any one should teach you; as his anointing teaches you about everything, and is true, and is no lie, just as it has taught you, abide in him.

And now, little children, abide in him, so that when he appears we may have confidence and not shrink from him in shame at his coming. If you know that he is righteous, you may be sure that every one who does right is born of him.

See what love the Father has given us, that we should be called children of God; and so we are. The reason why the world does not know us is that it did not know him. Beloved, we are God's children now; it does not yet appear what we shall be, but we know that when he appears we shall be like him, for we shall see him as he is. And every one who thus hopes in him purifies himself as he is pure.

Every one who commits sin is guilty of 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 sins; no one who sins has either seen him or known him. Little children, let no one deceive you. He who does right is righteous, as he is righteous. He who commits sin is of the devil; for the devil has sinned from the beginning. The reason the Son of God appeared was to destroy the works of the devil.