Let me give a good example of what I am talking about:
1 Clement (which is not scripture) talks about the resurrection in Chapters 25 and 26. He uses some historical "facts" to back up his claims--namely that there is a bird called the Phoenix and that every 500 years it dies, is reborn, and returns to Heliopolis. He cites it as evidence for God's ability to resurrect men. He even calls it a "wonderful sign."
Is the resurrection true? You bet! Has God proven through His creative work that the resurrection is true? Definitely. Is God without power to complete it? Most certainly not.
However, clement has successfully discredited himself by laying hold of that historical claim and citing it is evidence.
One of the best examples I can share with you is from Matthew 5:13, "You are the salt of the earth: but if the salt have lost his flavor, with which shall it be salted? it is thereafter good for nothing, but to be cast out, and to be trodden under foot of men."
Now, a man from Swaziland is going to read the surrounding text and come to the conclusion that he wants to be a Christian that is salt and light.
However, let's look at uses of salt back in that culture that don't necessarily fit in with our current understanding of salt...Some of these I have heard. Some I am just making up on the fly (although using historical facts)
1) The Rub-Off Salt plank. Back in the day, they would take drift wood from the dead sea and use it to salt their food by rubbing it on said food. Once it ran out of saltiness, they would throw it on their roof and men would walk on it. Interpretation: Don't let other people rub off on you and cause you to lose your saltiness.
2) The salt-rocks. Apparantely, there are rocks that are partially composed with salt and then composed with other materials. Once the salt is used up out of the rock, the remainder is useless. Interpretation: You can't be mixed with the world. You have to be pure salt in order to be affective.
3) The Jewish sacrificial salt. This salt was included in sacrifices and if it was missing, was not acceptable. Interpretation: If we are not salty, as Christians, we are unacceptable sacrifices to God.
4) The romans would sprinkle salt on enemy territory to prevent anything from growing. Interpretation: As the salt of the earth, we should be preventing the enemy from thriving.
5) Salt is tasty, and necessary for life. Interpretation: As Christians, we should be what makes this world worth living in--we should make the world taste good!
etc.
Now, I could plainly read. Or I can read into the Scriptures all this other nonsense that I received from outside of the Scriptures. Isn't that Eisegesis? Maybe I'll get something close. Maybe I'll totally miss the point.