They that are deceived are many, because “wide is the gate that leadeth to destruction, and many there be which go in thereat.” [Matt 7:13] This one thing is enough to detect the Antichrists and seducers, that they shall say, “I am Christ,” which Christ Himself is no where read to have said: for the works of God, and the word which He taught, and His power, were enough to produce belief that He is Christ.
For every discourse which professes to expound Scripture faithfully, and has not the truth, is Antichrist. For the truth is Christ, that which feigns itself to be the truth is Antichrist. So also all virtues are Christ, all that feigns itself to be virtue is Antichrist; for Christ has in Himself in truth all manner of good for the edification of men, but the devil has forged resemblances of the same for the deceiving of the saints.
We have need therefore of God to help us, that none deceive us, neither word nor power. It is a bad thing to find any one erring in his course of life; but I esteem it much worse not to think according to the most true rule of Scripture.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).