A Greek fable goes like this:
Jupiter, the chief of gods, was getting married and invited all the animals living on land and in water to attend the banquet. All the animals came to attend the feast but the tortoise didn't come. Jupiter was surprised at his absence.
After a few days, Jupiter came across the tortoise and asked him, "Why didn't you attend the banquet held in honour of my marriage? Were you all right?" The tortoise retorted, "I am a stay-at-home type of an animal and never care to attend petty affairs. Why should I trouble myself when there is no place like home?"
Though, the tortoise said something very true, the way he said it was very hurting. Jupiter felt hurt and cursed the tortoise, "Now, you will always carry your home on your back and never be able to unload it."
Still today, every tortoise carries his home with him.