The Tao asks you to clearly see the parallels between you and this naturally flowing substance that allows life to sustain itself. Live as water lives, since you are water. Become as contented as the fluid that animates and supports you. Let your thoughts and behaviors move smoothly in accordance with the nature of all things.
Try squeezing a handful of water, and see how quickly it disappears. But relax and let your hand flow in the same water, and you have the experience of the water as long as you like.
Study water. Try to grab a hold of water, and it will always elude you. You just have to let yourself be in it. It's soft, and it overcomes anything that's hard. Put the hardest substance - say, titanium - out there, and let water flow over it. Eventually, patiently, peacefully, the water will just wear it away. Also, water will enter anywhere - through any opening at all. So, let yourself be like that. God is in nature, everywhere and always. And we have so much to learn.
God is like the ocean and we're like that glass of water. We try to sustain life and do all that the source tells us that we are capable of doing, but if we do it alone, we wither away and collapse instead.