2 John 1:9

Whosoever transgresseth
Not the law of God, of which everyone is a transgressors and that daily, in thought, word, or deed; but who passes over the rule and standard of doctrine, the word of God, and will not adhere to that, nor walk according to it, but rejects and despises that rule:

and abideth not in the doctrine of Christ;
which he received from his Father, and delivered to his apostles, and of which he is the sum and substance; the doctrine which is concerning his person as the Son of God, and as truly God, and the union of the two natures, divine and human, in his one person; and concerning his office, as the Mediator, surety, and messenger of the covenant, and as the prophet, priest, and King of his church; and concerning his incarnation, obedience, sufferings, death, resurrection from the dead, ascension to heaven, session at God's right hand, intercession for his people, and second coming to judgment; concerning peace and pardon by his blood, atonement by his sacrifice, justification by his righteousness, and complete salvation by him: this is (xyvmh Klm lv wdwmlt) , "the doctrine of the King Messiah", or the Messiah's Talmud ^F8, to use the Jewish phrase, and which agrees with John's. Now, whoever has embraced and professed this doctrine, but errs concerning it, and rejects it, and abides not in it, as Satan abode not in the truth, appears to be of him:

hath not God;
for his Father, but the devil, the father of lies; he has no true knowledge of God, for there is none but in Christ, whose doctrine such an one has denied; nor has he, nor can he, have communion with him, nor any interest in him.

He that abideth in the doctrine of Christ;
as he hath received and professed it; neither can anything remove him from it, not the arguments of false teachers, nor the reproaches and persecutions of men, or the snares and allurements of the world:

he hath both the Father and the Son;
he has an interest in them both, and has knowledge of each of them, and fellowship with them. The Alexandrian copy and the Vulgate Latin version leave out the phrase, "of Christ", in the preceding clause, and only read, "in the doctrine"; and the Syriac version, "in his doctrine"; the sense is the same.