Here again we note the Prophet s unique method of teaching. He seizes the opportunity to remind his questioners of the hereafter. For the incurable illness in nothing but old age. We should not be surprised at the fact that the Prophet calls it an illness. After all, what does illness do to man if not to weaken him and sap his strength.
Old age does exactly that, although it is caused by no germ or virus.
When the Prophet says that old age is incurable, he means that it is a terminal illness which ends in death. When one dies, one has to face the reckoning. If he has done well in life, he is a winner. If he has not, he is an absolute loser. The Prophet s answer, therefore, serves as a reminder to people to do well before they are overtaken by this incurable illness which is bound to take its toll and terminate the life of its victim.