The psalm in today's reading has a line which has always seemed rich to me: “The man who follows not the ways of the wicked... is like a tree planted near running water, that yields its fruit in due season and whose leaves never fade.” 

This individual is “planted,” set in place by someone who presumably knows what he is doing, and the nearby water is running, alive.  The tree, or each of us, has all that it needs at all times even though that support is not immediately visible.  It is simple and clear, nearly invisible, and yet it is what the tree, or each of us, yearns for and cannot live without. 

And we could say much the same thing about the invisible light that is also essential for such life.

Such a tree yields fruit, not simply enjoying its dependable and satisfying condition, and it yields that fruit in due season, but is there such a thing as the unfading leaves which the psalm mentions next?  I would think that fruit trees are cyclic and shed their leaves on an annual basis in preparation for the next fruit-bearing cycle (but what do I know?  I'm a city boy), and I would guess that this suggests that this tree does not produce fruit only once a year but does so on a regular and steady basis. 

Take a look at Ezekiel 47:12 and Revelation 22:2, which pick up on this idea.  The trees in these passages are obviously symbolic, possibly of us, and go well beyond what we expect of the trees in our ordinary lives. Considering these verses in the respective contexts might help develop some of the implications of this psalm verse for us... 

To cut to the chase: are we like the tree of the psalm?  God has planted us in the time and place that he thought best for us, gave us just the gifts that he thought we would need, and wants us to flourish and to bear fruit for others as a regular event – and I would dare to say that he expects or at least hopes for fruit from us both in season and out (2 Timothy 4:2; Mark 11:12-14).  We are able to do so only because we have that almost invisible but radically necessary support from our God that we call “grace” – if we open ourselves to it.