Right from earliest childhood we are eager to know things. Because of this we learn a great many things, some of which will be to us and some of which will not. When we grow up, we get involved in some occupation and absorb information about it; and as we do, the occupation becomes a way for us to be useful, and we begin to love it. This is how our love of being useful begins; and this love leads us to also love the means that allow us to do our occupation and make it effective.
This process applies to everyone in this world because we all have some occupation to which we progress, beginning from the service we envision as a goal, through the means, to the actual service that is the result. However, since this service end its means have to do with life in this world, loving it is an earthly type of love.
from Life/Faith: Teaching for the New Jerusalem on Faith, Section 25