What Would Jesus Do? Or, more relevant:
How Would Jesus Drive?
Where is it written, that just because someone has strong enough convictions about their chosen religious views that they apply stickers and signs to their motor vehicle, that they also are required to drive BELOW the posted speed limit?
I realize that I'm unfairly singling out Christians (so far), but that's only because they are the only group that (so far) chooses to mark their vehicles with slogans and sayings and scripture quotes, for the enjoyment of (implied) non-believers who are stucketh behind thou in thine traffic. I'm sure there are Muslim, Jewish and, who knows, Zoroastrian, bumper stickers out there. I just haven't ever seen one in this area in my 44+ years of existence.
So, speaking to this select few demographic: Please. Jesus would want you to get where you are going in a most expeditious manner. Safely, of course. But expeditious, no less. Remember, slowness is a clear indication of Sloth, one of the well-known 7 deadly sins. So please: Do yourself, your employer, and your fellow drivers, a most generous and Christian favor and drive AT LEAST at the posted speed limit. If you really want to spread the love and joy, add 10 MPH on top of that. We all thank you. :)