Any one who goes ahead and does not abide in the doctrine of Christ does not have God; he who abides in the doctrine has both the Father and the Son.

Πᾶς ὁ προάγων καὶ μὴ μένων ἐν τῇ διδαχῇ τοῦ Χριστοῦ θεὸν οὐκ ἔχει· ὁ μένων ἐν τῇ διδαχῇ, οὗτος καὶ τὸν πατέρα καὶ τὸν υἱὸν ἔχει.

Later Commentaries

George Leo Haydock (1774-1849)

Haydock Catholic Bible Commentary: 2 John

We here see the reward for adhering to the Catholic faith, and the condemnation for revolting from the received truth. The apostles, and their lawful successors in the ministry, determine the true doctrine in points which innovators call into controversy, which being once done and declared to the faithful, they need no other mark to know a false teacher, but that he cometh with another doctrine than that which has been delivered.