This verse tells us that no matter what we have to do today, the work you do can and should be dedicated to God. It doesn't matter how mundane the task may seem or if no one will ever knows you did it...God knows and He appreciates it. 

And, you also never know when another person will be greatly blessed years from now by your diligence today, Think of it like this. Do you know who dug the ditch your water line runs through to get to your house? Unless it was you, probably not! But you sure appreciate him at 2am when you need to give your toddler some cold water to wash down the Tylenol you gave her when the thermometer reads 103 F. Every drop of sweat matters to God when the work you do is dedicated to His glory.  

- Sam Guilliams -