A colourful representation of the Taoism concept of being like water where Lao Tzu takes water as a metaphor for this assertion; water is soft and flexible, but also has the power to erode the hardest materials like rock and metal. This is well said in Bruce Lee's quote:"
Empty your mind.
Be formless, shapeless, like water.
You put water into a cup, it becomes the cup.
You put water into a bottle, it becomes the bottle.
You put it into a teapot, it becomes the teapot.
Now water can flow or it can crash.
Be water, my friend."