We may also sense the greatness of the Prophet's command to use the Miswak in his words: "The Siwak is purifying for the mouth and pleasing to the Lord." (Narrated by Ahmad and Ibn Majah; Saheeh)
The Prophet, peace and blessings of Allah be upon him, did not get up after a nap either at night or during the day without using the Siwak, and the Prophet, peace and blessings of Allah be upon him, urged his Ummah to use the Siwak all the time, when he said: "Were it not that it would be too hard for my Ummah, I would have commanded them to use the Siwak at the time of every prayer."
As is proved in the Saheehain, when the Messenger of Allah, peace and blessings of Allah be upon him, got up at night he would clean his mouth with the Siwak, and he also encouraged us to use the Siwak all the time, even when fasting. That is because of the great benefits that it offers to the mouth and teeth. These benefits include the following:
(1) It kills germs. Research has proved that it kills off at least five types of disease-causing germs that are found in the mouth, the most important of which is the streptococcus bacteria which causes some types of rheumatic fever (Brown and Jacob, 1979).
(2) It removes food remnants and yellowness from the teeth, and makes teeth shiny.
(3) It purifies the mouth by killing germs and treats wounds and inflammation of the gums.
(4) It prevents the growth of germs by increasing acidity in the mouth.
(5) It removes plaque before it becomes hard and affects the tissues.
(6) It prevents diseases of the mouth and teeth.
(7) It has been proved that it effectively reduces sugar levels and has an anti-cancer effect.
(from Islamic Medicine: The Key to a Better Life by Yusuf Al-Hajj Ahmad, Published by Darussalam)
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