The image is agricultural and it is doing more work than it first appears. A tree planted by streams of water, yielding fruit in season.
Notice that the tree is not straining. Nothing in the picture suggests effort. It produces fruit because of where it is standing, and it is standing there because someone planted it.
The verse before tells you what the water is. His delight is in the law of the LORD, and on His law he meditates day and night. Meditation here is not a technique. It is closer to chewing, returning to the same words repeatedly until they work their way in.
That is a slower relationship with Scripture than most of us have. We read to extract something usable and close the book slightly disappointed.
In season is worth noticing too. Not constantly, not on demand. Fruit arrives on a schedule the tree does not set.
Stay near the water. The rest follows from location.
