As I dug deeper into your site I had to cover it back up with dirt. Why, beloved are you referencing the NIV Bible in any aspect with in your site??!! TEST THE SPIRITS AND SEE IF IT IS OF HIM… Our Adversary has omitted many many Scripture [from the NIV] and has twisted the ones that remain! PLEASE do Your Research.
Oh… You are talking about some of the verses that are in the King James Version but which were not in the original Greek texts. Now I get it. I am sorry. I did not see your attachment. OK, so now I can reply.
As for Acts 8:37 none of the most ancient manuscripts include this material. The King James Version is the one which got it wrong. Only manuscripts after AD 500 or so even include this verse. The corruption is with the King James Version. In fact, no modern translation includes this verse as the consensus of all scholars is that this was not in the original and is a corruption. I believe that any fair-minded person doing research on this particular verse will reach the same conclusion.
The same can be said for John 5:4. Literally none of the earlier manuscripts include this interpolation. It was clearly added later by someone who was copying the New Testament as an explanation of the passage. The first manuscript to include this little verse is from about AD 800. No early Church father mentioned this verse when quoting the New Testament simply because it was not even in the New Testament. The Textus Receptus of Erasmus included it because his oldest manuscript was from about AD 1100, by which time some small corruptions had appeared in the Bible. As far as I know, no scholar who understands the evidence will disagree with the fact that the King James Version is wrong on this one.
The same kind of evidence applies to all of your examples, except to a varying degree. For example, Acts 15:34, Mathew 17:21 and Matthew 23:14 are interpolations as well based on the manuscript evidence. Notice that all NIVs include these passages, except that they are in the margins. Nothing is being hidden here. The translators simply are noting that the preponderance of the manuscript evidence is that these are interpolations (added by a scribe as an explanation, but not in the original), so most likely were not in the original. Despite this, the translators include them in the margin so that any Bible believer can judge for him or herself as to the original. In none of these cases is the meaning of the New Testament in any significant doubt. There was no effort on the part of these early scribes to twist the scripture.
So, the NIV does not remove anything from the Bible. In fact, in every case in which a particular verse is moved to the margin it is because the evidence supports that this verse was not in the original, but the publishers of the NIV (and many other translations which also do similar things) move the more questionable verses to the margins. It is wise of the publishers of the NIV to not simply remove these verses, but to put them in the margins so that the readers can decide for themselves. You seem to be claiming that there is a willful attempt to deceive, supported by Satan, but this is not consistent with the facts.
The translation with the most corruptions is the King James Version. This is not due to any fault on the part of the translators of this version. They simply had a lot less evidence than we have.
You say to test the spirits. I do not understand what you mean by that. I say that we should test the evidence and allow the evidence to inform us about what is the truth about the copying of the Bible. Almost certainly Acts 8:37 and John 5:4 were not in the original New Testament. The evidence on this is a slam dunk. I can allow “the spirits” to tell me or I can allow the evidence to tell me. Not a single well-informed person believes that John 5:4 was in the original, so I believe that this is almost certainly the case.
I apologize that I initially failed to see your list of verses which are in the margins of the NIV.
I hope this helps.