It is very interesting to read the entire second chapter of 2 Thessalonians to get the context, which is the great apostasy (today?), and the “strong delusion”, or “operation of error” that God will send so that those “who love not the truth will believe a lie”. It is interesting to consider how those today who “love not the truth” justify themselves based on Vatican II (the strong delusion?).
The antidote given by the apostle for not being led astray by the strong delusion, or the “operation of error”, depending on the translation, is to “hold fast to tradition”.
I personally think Vatican II may indeed be the strong delusion spoke of by St. Paul nearly 2000 years ago. And it is not just the “spirit of Vatican II”, but the council documents themselves, for they lend themselves to being interpreted in a manner contrary to what the Church teaches, even when they don’t explicitly teach what they appear on the surface to teach. Therefore, due to the ambiguous and often misleading manner in which the documents are written, those who love not the truth believe lies.
How many people today, for example, adhere to errors condemned explicitly in the Syllabus of Pius IX because they think Vatican II taught the contrary? Here’s just one of the errors from the Sallabus that many today adhere to:
[It is an error to believe that] “Every man is free to embrace and profess that religion which, guided by the light of reason, he shall consider true” (Syllabus #15).
Thanks for Vatican II, or at least what everyone thinks Vatican II teaches, most Catholics today have accepted that formally condemned error as true.
Hopefully the talks between the SSPX and Rome will result in a “clarification” of some of the Vatican II documents.