Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: Sir, my concern is not whether God is on our side; my greatest concern is to be on God's side, for God is always right.' - Abraham Lincoln
This tweet contains emotions: 
joy, optimism, trust