Practicing mindfulness, we begin to recognize the impermanence of everything. With pain, we are able to see that our pain is not permanent, whether physical, emotional, mental, or spiritual. When we recognize our pain will pass and life will go on, we are able to let go of our notion of the pain, and stop resisting it. Our instinctual resistance to pain causes even more suffering, and when we are able to cease this reaction, we find peace.
When we practice mindfulness, we also see the impermanence of our pleasure. We may look at the flower here, and notice the beautiful drops of dew sitting on the petals. However, we all know that as the sun rises in the sky, the dew will evaporate. We know that the pleasant feeling is impermanent, and if we are able to recognize this from the beginning, we drop attachment to our pleasure. If we are able to drop our attachment to pleasure, we cease behaving in ways that cause us pain.
Mindfulness teaches us that life is beautiful in this very moment, regardless of concepts of pain and pleasure. When we try to avoid the pain or cling to our pleasure, we find suffering. When we look at our pain as impermanent, and effecting but a temporary body, we are able to pass through it without difficulty.