Task: Categorize the tweet's emotional expression, classifying it as either 'neutral or no emotion' or as one or more of the specified emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that reflect the tweeter's state of mind.
Tweet: Only God knows why things happen, sometimes it's just hard to understand. #sad #prayingforyou
This tweet contains emotions: 
optimism, sadness