As human beings, we have a need for security. Time is fleeting and despite our best efforts, those moments we recognize ourselves as truly happy in our earthly lives only last for a brief glimmer. We desire permanence, but we also desire spontaneity. Think, for example, of a hypothetical situation in which you could "freeze" time so that a state of happiness could last forever. Should this happiness outweigh the happiness of others in the future? It seems not, and moreover, the actions we perform in the future will potentially contribute to the happiness of others in such a manner that we are needed to continue through time.
There is, then, a desire for spontaneity along with a desire for permanence. It is in the permanence of God's love that we find satisfaction for both desires. We endure through time, God's creation, all the while knowing that we rest in God's love.