2 John 1:4-9

I rejoiced greatly that I found of thy children walking in truth, as we have received a commandment from the Father. And now I beseech thee, lady, not as though I wrote a new commandment unto thee, but that which we had from the beginning, that we love one another. And this is love, that we walk after his commandments. This is the commandment, That, as ye have heard from the beginning, ye should walk in it. For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist. Look to yourselves, that we lose not those things which we have wrought, but that we receive a full reward. Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son.