Torah 224 · תורה רכ״ד

Even those who are distant from the tzaddik receive vitality and light from him by means of his shading them. This is analogous to a tree, which has branches, bark and leaves; and they all draw life from the tree. There are also grasses that are distant from the tree, so that it seems as if they receive no vitality from the tree. But in truth, they too receive vitality from it, because the tree protects them and shades them from the sun.

Similarly, in relation to the tzaddik there are [those] in the aspect of leaves, branches, etc., as is explained elsewhere. And even those who are distant receive vitality from him, by his shading them, like the tree, as explained above.