"Dan: A Serpent by the Way..." is posted on the sidebar

The first half of Pastor Garrison's 40-ish minute sermon focuses upon several of Jacob's twelve sons.  The second half, gets into how one can, and does, end up "unhorsed" not by the drunkards and the gamblers, but from some venom, that shot from a few pews ... somewhere thataways.

In short, we expect unsaved people to invalidate - or just be plain harsh, but even born-again people can get snitty - though saved people know back-biting is sin, and so, pray and strive to get the heck over their sweet little selves.  

Thing is, 2nd Peter, Chapter 3, and the Book of Jude, reminds us, that just because you're wearing a lab coat, doesn't make you a biologist.  So yeah, Christians need to "be wise as serpents, harmless as doves."  

"For there are certain men crept in unawares, who were before of old ordained to this condemnation, ungodly men, turning the grace of our God into lasciviousness, and denying the only Lord God, and our Lord Jesus Christ."  Jude 1:4

"Behold, I send you forth as sheep in the midst of wolves: be ye therefore wise as serpents, and harmless as doves."  Matthew 10:16