Once Abdullah Bin Jafar (ra) was passing through a forest when he went by an orchard where an Abyssinian (Ethiopian) slave was working. Someone brought him his food and, at the same time a stray dog came into the garden, and stood by the slave, who threw a loaf of bread to the dog, which ate it but did not go away. The slave-boy threw it a second loaf and a third one, thus letting it eat the whole of his daily provision of food, keeping nothing back for himself. Abdullah bin Jafar, who had been watching this, said to the boy, "How much bread do you get as your daily ration of food?" The boy said, "I get three loaves everyday, as you have just seen." Ibn Jafar asked, "Then, why did you prefer a dog to yourself and feed it all the three loaves?" The boy said, "There are no dogs living round here. The poor creature must have travelled a long distance to reach here and it must be feeling very hungry. So, I felt ashamed to send it away, without serving it any food." Ibn Jafar said, "What will you have for food today?" The boy said, "I shall go without food for a day, which I don't mind." Ibn Jafar said to himself, "People criticise you for spending too liberally, but this slave-boy is far more generous than you." After this he came back to the town and, after purchasing the slave-boy, the garden and all the other effects therein from the owner, he set free the slave-boy and gave him the garden as a gift.
Source: It-haaf; also found in Virtues of Charity Part II, translated by Abdul Karim.
Islam is the religion of mercy towards the creations and obedience towards the Creator. Let us practise it fully.