I've just had a very interesting conversation with my mother, that essentially came down to us thinking and chatting about what motivates us to do the things we do (specifically, I take photos and do a couple of other things, she makes greetings cards - and very nice ones, too).
Some things I do simply for the pleasure of doing them, like reading a book or watching a film. With others, specific purpose helps a great deal in terms of motivation and focus: I tend to go out photographing with the idea to visit a particular place and/or take a particular kind of picture, and afterwards the 'carrot' of seeing the images pushes me through the less enjoyable slog of tempering solutions and hunching over the bath inverting a developing tank.
But what else keeps me doing all the other things I do? What motivates me throughout the days of life? The Sunday School answer is of course that I'm trying to become more like Jesus - which is accurate and true, but even though I spend and have spent much time communicating with others about my faith and its driving force in my life, that still remains a distant goal that is expressed to varying degrees, well and poorly, through all the other things I worry about and get on with.
I want to be good for my wife and for my family. I want to be responsible with all that I have - personally and in common with those around me. I desire a certain amount of material comfort, but more than that I want to decide rightly at those points where that desire collides with the faith, good, and responsibility already mentioned. I want to use what I have, material and otherwise, to best and most Godly effect.
And all but one of those motivations is depressingly easy to neglect, ignore, forget about. But those are what I want to be able to say I chase after.
But store up for yourselves treasures in heaven, where moth and rust do not destroy, and where thieves do not break in and steal. For where your treasure is, there your heart will be also.
The eye is the lamp of the body. If your eyes are good, your whole body will be full of light.