Summary: A sermon on Proverbs 26:27 (Introduction taken from Ronnie Brown http://www.sermoncentral.com/sermons/whoso-diggeth-a-pit-ronnie-brown-sermon-on-salvation-83999.asp) (Outline taken from Pulpit Commentary)
At first glance at this verse I think of the oddest image in my mind. I think of a cartoon. The verse at first glance seems comical, very much like the sly coyote. The roadrunner and coyote cartoons are great and so funny. One that is scheming and designing and laying out a trap for the roadrunner. Much effort was placed in to the digging of that pit. Much toil went into the labor of rolling stone. With every shovel of dirt, the coyote thinks, “I’ve got him this time!” With every sweat filled inch the stone is turned, he thinks, “I can almost taste him. He’s mine!” But in the end, the result is the same. The coyote is distracted, drawn away, or duped, and it is not long before he finds himself looking up from the bottom of his own pit or squished in to a funny paper thin shape. But just as soon as the disaster takes place, we find him in the next scene, doing the same thing all over, lighting a fuse that will explode in his own face or painting a wall that he himself will run straight into. But as I read the verse again, I am shaken to the core that this is a serious thought from the Word of God
This is the picture in this proverb. One may have dug a Indian tiger trap to catch some wild animal or make a prisoner or victim of his enemy. He covers it with a tarp, dirt and leaves. Later on, he forgets where the trap is, he falls into it himself to his doom.
Another picture here is of rolling a stone against the enemy, the stone falls back and crushes the author of the mischief.
Thesis: Let’s talk about some cases where this might happen, and then the principle that underlies it.
II. Cases where it might happen
Those who deceive others are likely to be caught in their deception.
Sir Walter Scott- Oh what a tangled web we weave when first we practice to deceive
a web is what is woven by a spider, and its function is to trap flies with its stickiness; the more they wriggle to get away, the more they entangle themselves in it. Scott is warning us that the liar spins and weaves his own trap for himself, not realizing he has done so until he's caught
Plato- The worst of all deceptions is self-deception.
They get used to falsehood until they now longer can distinguish truth from error.
They become like Pilate who asked, “What is truth?” when truth was staring him right in the face. No absolute truth, no such thing as truth.
Luke: "You lied to me. You said that Darth Vader killed my father."Obi-Wan: "When Anakin Skywalker turned to the Dark Side of the Force, the good man that was your father ceased to exist. So, what I told you was the truth -- from a certain point of view." -- Star Wars: Return of the Jedi - 1983
There are benefits to relativism. It means that we can never be wrong. As long as it is right for me, I’m right even when I’m wrong!
Exodus 20:16 (quickview)  says that we shall not bear false witness against our neighbor. This implies that the truth or falseness of a statement can be tested by whether it checks out with the facts.