I am so shook by something my friend Trent posted on his blog, I felt I had to share it here:
[A man] once said,
“It is thirty years that I have been seeking forgiveness for one phrase, ‘Praise be God’s’, that I allowed to pass my lips.”
When asked to explain he replied,
“One night the marketplace caught fire, and I left my house to see if the fire had reached my shop. When I heard that my shop was safe, I said, ‘Praise be God’s’. Instantly I was brought to my senses with the realization that, granted my shop was unharmed, should I not have been thinking about others’?
A Mercy Case 
This is a story narrated by Saadi Shirazi in Bustan (first chapter; Concerning Justice, Counsel, and the Administration of Government)