The first task of the interpreter is called exegesis. Exegesis is the careful, systematic study of the Scripture to discover the original, intended meaning. This is basically a historical task. It is the attempt to hear it as the original recipients were to have heard it, to find out what was the original intent of the words of the Bible.
This is where almost all bad interpretation starts from. EXAMPLE: Some say, "Jesus never claimed to be the 'Son of God', he claimed to be the 'Son of Man'." Is this true? Yes and no. He did refer to himself as the Son of Man, but he was refering to the Messianic figure in Daniel. This was obvious to his original audience, but it's not to us. So, in order not to fall into interpretive failures we need to be careful. So, if the original author didn't mean for what he said to be taken literally, then it would be poor exegesis to take it literally. And likewise, if he meant for something to be taken literally, then by all means it should be taken literally.
One of my favorite theologians, John Piper, always says "Dig and you get diamonds." This is very very true. Have any of you read Mark? I mean REALLY dug into Mark? I have with a group of people. We use unmarked RSV manuscripts (no chapter #s, verse #, or paragraph breaks). We're not allowed to use any "interpretive" source, so no commentaries. And we try hard to forget anything we've ever heard about the Gospels and the NT all together. In fact, we're not even allowed to use anything in the bible except for the Old Testiment. We can't even look at the NT. Then, using only concordances, and bible dictionarys and various other historical sources, we dig through it all, little piece by little piece. Let me tell you, there is some crazy confusing stuff in Mark. But, after struggling through it all, I've never been more convinced of the inspiration of Scripture. Read throught it, there's about a hundred questions that need answering in just the first chapter. Dig and you get diamonds (Mark ch4).