water or rocks? Both please!

I was recently asked if I would rater be a rock or water. Of course me being the way I am I immediately yelled out "A rock!". With a look of not quite disapproval my teacher calmly looked at me and said, "Tell me why you choose that." I replied that a rock is strong, dependable and mostly unchanging." She smiled and replied "yes that is true, now tell me about water." I said well "Water flows, and is never still." She smiled again and said "Very true." Then she began to tell a story, a story about water and rocks. While the rocks sit in one place and are unmoving, they are indeed constant but they are slowly being changed by the water. A rock is hard and unwilling to move, but none the less the water calmly, patiently and quietly changes the rock, most of the time without the rock ever knowing it is being changed. After she read the story with the grand canyon of course being the main example I quietly smiled at her and when she asked me what I'd rather be I replied "the water." "Good choice" she said as she smiled at me. Then I said "and the rock as well." She looked at my with a question on her face, clearly not expecting this answer. She said "Go on." And I told her that I would rather be the rock at times and the water other times. There are some times in our lives where we need to be a rock because a rock in the river is not taken into the current with all of the debris and garbage. A rock is strong and sturdy, never faltering in what it believes in or thinks. Now the water is good to be at times because it is better to do and lead by example than to try and make someone change. Now my teacher is not a Christan and she has voiced many times that Christianity is not allowed in the classroom, but I find this idea interesting because is this not a Biblical principle? Did Christ not lead by example as the water, quietly changing people's hearts and minds. He was also the rock however, because he refused to be swept down the river with the debris the water carried along with it. I love the analogy of water and rocks, but I want to be both, not one or the other.