In a previous article I addressed the issue of Codex Montfortianus and Erasmus and showed that the so called “British” Codex that Erasmus used could not be Codex Montfortianus.  I was pleased to find out that Dr. White responded to my article during his Dividing Line on June 16.  However, his comments were not as helpful as I had hoped.  He has completely missed the point of my post and did not address the specific issue I was dealing with.  In an article on his blog and in his book King James Only Controversy, Dr. White uses the argument that Erasmus used Codex Montfortianus.  The point of my article was to specifically address the myth of Erasmus’ use of Codex Montfortianus to justify the inclusion of the Comma Johanneum in 1 John 5:7.  It was not intended to be used as definitive proof for the authenticity of the Textus Receptus.
I have also received comments asking me about a different section of Erasmus’ Annotations where he quotes from the text he used to include the so called Comma Johanneum of 1 John 5:7.  At first glance this evidence would seem to refute my arguments.  However, when examined it only goes to reinforce my argument that Codex Montfortianus was not used by Erasmus.
The information in this article was first pointed out by Bishop Thomas Burgess in his book A Letter to the Reverend Thomas Beynon Archdeacon of Cardigan, In Reply of the Literary Character of Professor Porson, By Crito Cantabrigiensis and In further Proof of the Authenticity of 1 John, v. 7.  On page 6-7 he addresses a problem with attributing a “Dublin manuscript” (which is Codex Montfortianus) to Erasmus’ “British Codex”.
In his annotations, Erasmus makes this comment:

“But, not to dissemble any thing, one single Greek manuscript hath been discovered in England, wherein what is wanting in other manuscripts is found thus:

ὅτι τρεῖς εἰσιν οἱ μαρτυροῦντες εν τῷ οὐρανῷ, πατήρ, λόγος, καὶ πνεῦμα, καὶ οὗτοι οἱ τρεῖς ἕν εἰσιν.  καὶ τρεῖς εἰσιν μαρτυροῦντες ἕν τῇ γῇ, πνεῦμα, καὶ ὕδωρ καὶ αἷμα ^m εἰ τὴν μαρτυρίαν τῶν ἀνθρώπων &c. Yet, I know not by what accident, what is in our Greek copies is not repeated here, καὶ οἱ τρεῖς εἰς τὸ ἕν εἰσὶν, and these three agree in one.”  For the Latin portion I have quoted from James Jordin’s The Life of Erasmus, Vol 2, p. 231-232.

This is part of the section that first appeared in Erasmus’ 3rd edition.  The section I referenced was not included until the 4th edition.
As I said earlier, at first glance this seems to disprove my argument.  But a closer examination will show that this does not prove that Erasmus used Codex Montfortianus.  I have included again a picture of Codex Montfortianus for comparison.  If you look closely you can see that there is actually several significant differences between Erasmus’ citation and the Codex.
In verse 7, Erasmus does not include “ἅγιον” (holy) after πνεῦμα, as Codex Montfortianus does.
As well, in verse 8, Erasmus does not include the article οἱ before μαρτυροῦντες.
This again shows that Erasmus did not use Codex Montfortianus.  Now why is his comments on the British Codex including the last phrase of verse 8 and his citation of a manuscript found in “England” different?  I don’t have an answer to that question at the moment.  What I do know is that neither of Erasmus’ comments can be used to prove that he used Codex Montfortianus.  Both readings are different.  Based on the evidence, Erasmus could not have used Codex Montfortianus to include 1 John 5:7 in his 3rd edition of the Greek New Testament.