One day a lady came to Fatima (as) and said ‘I have a weak old mother who does not know a few problems about her prayers. She has sent me towards you to question you about them.’ Fatima answered her (questions) and the number of her questions reached to ten and Fatima (as) replied to all her questions.
Then she (the woman) got a shamed because of the high number of her questions and said, ‘Oh daughter of the Prophet (as) ‘I do not want to put you to more inconvenience than this.’ Fatima (as) said, ‘Ask me what you do not know. Have you ever seen a person who is one day hired to carry a heavy thing to the roof top from the ground for an amount (equal to) a thousand dinars (nearly a hundred thousand miskal (unit of weight) of gold) and he may feel tired?’ She said ‘No.’ Fatima (as) said ‘I have been hired by Allah to get a wage which if the space between the earth and the sky were filled up with pearls still it would be more than that for each of the questions I may answer you. Therefore, I deserve it that I must not feel tired and exhausted.’
BIHAR UL ANWAR. VOL 2