One must see in every human being only that which is worthy of praise. When this is done, one can be a friend to the whole human race. If, however, we look at people from the standpoint of their faults, then being a friend to them is a formidable task.
It happened one day in the time of Christ—may the life of the world be a sacrifice unto Him—that He passed by the dead body of a dog, a carcass reeking, hideous, the limbs rotting away. One of those present said: ‘How foul its stench!’ And another said: ‘How sickening! How loathsome!’ To be brief, each one of them had something to add to the list.
But then Christ Himself spoke, and He told them: ‘Look at that dog’s teeth! How gleaming white!’
The Messiah’s sin-covering gaze did not for a moment dwell upon the repulsiveness of that carrion. The one element of that dead dog’s carcass which was not abomination was the teeth: and Jesus looked upon their brightness.
(‘Abdu'l-Baha, 'Selections from the Writings of ‘Abdu’l-Baha')