As I was growing up, I was something of a know-it-all. Encyclopedias, record books, and almanacs were my favorite reading material, so I did know quite a bit of (marginally useful) information. Combine that with the fact that I always wanted to correct people when I perceived they were mistaken and you can see how I would have been annoying.
So having been trained in biblical studies, I am probably an even worse know-it-all, though more useful for the edification of the church. I sometimes encounter teachings in sermons or Bible studies or praise songs which my critical mind tells me are problematic for whatever reason: exegesis of the English text, problems with the use of original languages, disregard for context, theological discrepancy, etc. And here is the dilemma I face: when is it helpful for me to offer correction when I encounter such mistakes?
I was just recently listening to a teaching which I thought was problematic (in this case, it was due to the speaker exegeting his English translation). In my opinion, the point he was making was proper, godly, and edifying. The problem was simply that the scripture he was referencing was by no means making the same point. This is a fairly easy case which is the most common, and I handle it by letting it go. Perhaps the mistaken individual would truly appreciate the correction, but it is not such a big problem, and it is probably best for my own ego to forgo the correction. Now the real test would be if a mistaken teaching was more significant - if it were being applied in support of a heterodox teaching or ungodly behavior. In that case I might feel compelled to correct the teacher and request that he correct his audience (and such a move would have to be in conjunction with proper church leadership procedures). Needless to say, I hope I am never in that position, but I suppose it is an implication of my training for which I need to be prepared.