Accepting and defending only the 66 book Anti-Christ Pharisee Approved Luther Subset rather than the entire Bible that includes the entire Old Testament is nothing less than asserting that the Holy Spirit is imperfect because the Holy Spirit cannot and did not protect His Holy Word from including error for over fifteen hundred years.
"And whosoever shall speak a word against the Son of man, it shall be forgiven him: but he that shall speak against the Holy Ghost, it shall not be forgiven him, neither in this world, nor in the world to come."
Matthew 12:32
Anyone who falls for and repeats the lie (in any of the many forms it takes) that the anti-Christ Pharisees and/or Martin Luther are perfect but the flawed, imperfect, Holy Spirit cannot and did not protect His Holy Word from the inclusion of error is proving they're under the strong delusion that will lead them to their own destruction.
Their being under a strong delusion in no way mitigates their blaspheming of the Holy Spirit.
Yes, Rashputin, 66 was such an unfortunate number to settle upon considering the Book of the Apocalypse. You would think it would have been 65 or 67. But maybe God permitted the Bible to be whittled to 66 books to give a sign to the perceptive of where every man as an authority unto himself would lead in the End.