Who knows this sentence: If we, like before, green as water, green as water

This sentence came from a novel, Sword Snow Stride ". The original text was " If we were as green as water, as green as water." It meant that if we were once as pure and kind as before, then the friendship between us should be as long as the green grass in the water. This sentence in the novel expressed the protagonist's nostalgia and emotion for the lost friendship, and also hinted at the protagonist's thoughts in the future when facing life difficulties.