How does John 16:13 justify the doctrine of infallibility?

**John 16:13**: > (KJV) Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come. > > (NLT) When the Spirit of truth comes, he will guide you into all truth. He will not speak on his own but will tell you what he has heard. He will tell you about the future. I've often heard John 16:13 quoted as an argument for the various "infallibility" doctrines, be it Biblical infallibility, infallibility of the ecumenical councils, or general Church infallibility. In particular there is great emphasis placed upon the fact that the Holy Spirit will "guide you into all the truth." In fact I have heard it stated that if you believe that the Church can err, then you believe Christ was lying when he said the Holy Spirit would guide the Church to "all the truth," not "some of the truth." Yet a plain reading of that verse does not seem to require infallibility. "Guide" seems to imply a process, and one not necessarily free from error. If someone is being guided to a final destination they may still get lost along the way, perhaps even be allowed to do so. The verse just seems to be assuring us that in the end the Holy Spirit will bring us to "all the truth." So am I missing something? Is there something that has been lost in translation? Is there extra-Biblical commentary somewhere amongst the Church Fathers that more thoroughly explains the verse? I am particularly in the Catholic position, but I would also be interested in the Orthodox and Protestant interpretations as well.