Irenaeus — Against Heresies 5.30

Although certain as to the number of the name of Antichrist, yet we should come to no rash conclusions as to the name itself, because this number is capable of being fitted to many names. Reasons for this point being reserved by the Holy Spirit. Antichrist's reign and death.

1. Such, then, being the state of the case, and this number being found in all the most approved and ancient copies [of the Apocalypse], and those men who saw John face to face bearing their testimony [to it]; while reason also leads us to conclude that the number of the name of the beast, [if reckoned] according to the Greek mode of calculation by the [value of] the letters contained in it, will amount to six hundred and sixty and six; that is, the number of tens shall be equal to that of the hundreds, and the number of hundreds equal to that of the units (for that number which [expresses] the digit six being adhered to throughout, indicates the recapitulations of that apostasy , taken in its full extent, which occurred at the beginning, during the intermediate periods, and which shall take place at the end) — I do not know how it is that some have erred following the ordinary mode of speech, and have vitiated the middle number in the name, deducting the amount of fifty from it, so that instead of six decads they will have it that there is but one. [I am inclined to think that this occurred through the fault of the copyists, as is wont to happen, since numbers also are expressed by letters; so that the Greek letter which expresses the number sixty was easily expanded into the letter Iota of the Greeks.] Others then received this reading without examination; some in their simplicity, and upon their own responsibility, making use of this number expressing one decad; while…

2. These men, therefore, ought to learn [what really is the state of the case], and go back to the true number of the name, that they be not reckoned among false prophets . But, knowing the sure number declared by Scripture, that is, six hundred sixty and six, let them await, in the first place, the division of the kingdom into ten; then, in the next place, when these kings are reigning, and beginning to set their affairs in order, and advance their kingdom, [let them learn] to acknowledge that he who shall come claiming the kingdom for himself, and shall terrify those men of whom we have been speaking, having a name containing the aforesaid number, is truly the abomination of desolation . This, too, the apostle affirms: When they shall say, Peace and safety, then sudden destruction shall come upon them. 1 Thessalonians 5:3 And Jeremiah does not merely point out his sudden coming, but he even indicates the tribe from which he shall come, where he says, We shall hear the voice of his swift horses from Dan; the whole earth shall be moved by the voice of the neighing of his galloping horses: he shall also come and devour the earth, and the fullness thereof, the city also, and they that dwell therein. Jeremiah 8:16 This, too, is the reason that this tribe is not reckoned in the Apocalypse along with those which are saved.

3. It is therefore more certain, and less hazardous, to await the fulfilment of the prophecy , than to be making surmises, and casting about for any names that may present themselves, inasmuch as many names can be found possessing the number mentioned; and the same question will, after all, remain unsolved. For if there are many names found possessing this number, it will be asked which among them shall the coming man bear. It is not through a want of names containing the number of that name that I say this, but on account of the fear of God , and zeal for the truth : for the name Evanthas ( ΕΥΑΝΘΑΣ ) contains the required number, but I make no allegation regarding it. Then also Lateinos ( ΛΑΤΕΙΝΟΣ ) has the number six hundred and sixty-six; and it is a very probable [solution], this being the name of the last kingdom [of the four seen by Daniel]. For the Latins are they who at present bear rule: I will not, however, make any boast over this [coincidence]. Teitan too, ( ΤΕΙΤΑΝ , the first syllable being written with the two Greek vowels ε and ι , among all the names which are found among us, is rather worthy of credit. For it has in itself the predicted number, and is composed of six letters, each syllable containing three letters; and [the word itself] is ancient, and removed from ordinary use; for among our kings we find none bearing this name Titan, nor have any of the idols which are worshipped in public among the Greeks and barbarians this appellation. Among many…