The top three rules of Hermeneutics (the art and science of Biblical interpretation) are: 1) Context; 2) Context; 3) Context. Before we can tell 21st century Christians how the Bible applies to them, we must first come to the best possible understanding of what the Bible meant to its original audience. If we come up with an application that would have been foreign to the original audience, there is a very strong possibility that we did not interpret the passage correctly. Once we are confident that we have come to the best possible understanding of what the text meant to its original hearers, we then need to determine the width of the chasm between us and them. In other words, what are the differences in language, time, culture, geography, setting and situation, etc. All of these must be taken into account before application can be made. Once the width of the chasm has been measured, we can then attempt to build the bridge over the chasm; what commonalities can we find between the original audience and ourselves, between our situation and theirs? Finally we can then find application for us in our time and situation.
Couldn't have said it better myself!