"Take heed that you do not do your justice before men, to be seen of them; otherwise you shall not have a reward of your Father Who is in heaven." (Matthew 6:1.)
The lesson taught here is purity of intention; we are to aim not at pleasing men, but God. So we are warned not to trumpet our alms, but to give so secretly that our left hand may not know what our right hand is doing. When we fast we are not to draw a long face; when we pray we are to close the door and pray in secret, and our Father, Who seeth in secret, will repay us.
Yet we are to do all this without scrupulosity.
There is a natural satisfaction in doing what we know we can do well. This is the very essence of the enjoyment we find in field sports or anything else we throw our hearts into. The cricketer is elated when he makes a good hit or a sharp catch, not so much for the sake of the applause it earns as from his very delight in the game. No one cares for a game at which he feels he is a duffer.
Yet, to secure ourselves against vanity and love of display, we must constantly raise our thoughts to God, offering all we do for His glory, taking disappointments and adverse criticism cheerfully, humbling ourselves, and being content to be held cheap, if it be for His greater honor.
-- Barraud, Meditations