Well I will say that Faith, that answer is extreemly good. It is a breath of fresh air, and a drink of clean water to see someone trying to explain things through reference of the text in question (The Holy Bible), and not throwing up what your church's leader fed you one Sunday, and just have some kind of blin dfaith that since he's a leader, God wouldn't allow him to lead the people astray (Even though if that is your belief in your heart, I respect it and agree it is possable, but I would question it's plausability.). Anyways, theres only one issue I have here..
It seems the only evidence supporting that there is a signal in the Bible to show these "signs" are not in effect anymore are some tenses in wording, and one charactor in the book giving another medical advice vs. healing him. Now those are valid, but a HUGE issue comes up... If I can look at one statement made by the supposive Son of God, and claim it is non-existent bcause of the author's tense of wording, I know being a fellow close reader you can agree there are many founding "Christian" beliefs (Although such little of the Bible contains the words of Christ, i'm rather surprised the religion following ALL the Holy Bible's words still carries that name instead of Biblianity or Apostlanity or Prophetanity) which can be thrown into the "In question" catagory.
The main thing is that there are no CLEAR indication of "Ok, ALL the following things do not apply to anyone but this one GROUP of people:", or even "ALL the stuff [enter name of Biblical charactor here] said no longer applies". So now if tense can't be used as an indicator, and the actual words of the book itself don't contain any clear instructions, we are left with this being a metephore.
Of course no religious leader wants to accept the notion of something in a religious text being metaphorical without it clearing so so. The reason is that now EVERY singel thing in the book instantly moves from the realm of "Literal, Infallable Fact" into that of "Questionable, Objectively Interpretable Writings". Most organized religions that accept parts of thier religious text(s) as metephorical have a safety-net clause in thier beliefs that allow for this, usually much like "God would not allow his word to be misintrpreted by those in a position of religious leadership, therfor my religous establishment's leader is 100% correct". If you believe this, thats fine, but there are a number circular-logic holes that arrise, and in a public discussion forum, can't stand as evidence (But in one's heart, one person's trash is another's treasure, and if it is a true heart's belief, I'd respect anyone INCREDIBLY more for following it rather than commonly accepted logic). Case in point, there are five basic outcomes that each can not be proved, and are up to your hearts belief:
1.) The Holy Bible is literal, and in this case the authors clearly provid clues as to when things apply/stop applying, and we must be attentive enough to see them, and use them to better our understanding of what is meant to be conveyed to us. (In which case, rather strong evidence has been laid forth that this poison-drinking/healing thing only applies to Jews, and was invalid after the first past-tense word was used to describe them, and from then on.)
2.) The Holy Bible is atleast in some places metephorical, and we have to use our own hearts or a faith (Like the Religious Leader being infallable, hence thier interpretations matching) to seperate metephore (then it's meaning) from literal fact. (So drinking poison/Healing may or may not be literal, depending on your heart/Leader's beliefs.)
3.) The Bible may be literal, but sense the tenses allow for tremendous amounts of various issues and timelines to come into question, and many times be validated/invalidated, iether an external method (Like an Infallable Leader) or individual interpretation must be used to sort out which were translational/bad authorship, and which were meant to be indicators to us. (Once again, your personal beliefs or that of a Leader.)
4.) The Bible is metephorical in it's entirety, and anything gained from it is a matter of believing your interpretation or someone elses (Religous Leader) to an extent or in complete entirety. (Once again, your interpretations and/or Leaders.)
5.) The Bible is literal, and this is what it is. If you can't heal people, or drink poison and be fine, then your obviously just not a good enough believer. (Bottoms up! You should be able to chug poison fine, and heal people. If you believe this option, please send me a YouTube video of you doing iether, as I would much enjoy watching it.)
Which do you believe? I don't know, but if you believe in the literal thing, i'd recommend testing your "faith" by attempting to heal someone rather than the second method.