Another word picture to help us better understand God is that he is the vine and we are the branches.
In this, God is revealed as the source of nourishment, the giver of life, and the means of support, sustenance, and existence.
For us, as vines, we are completely dependent on him for everything and can produce fruit only through him. Also, just as fruit trees are pruned, so to, we are pruned in order to be more productive. Additionally, note that branches that are unproductive are removed.