Someone who wants to perform the fast of the blessed month of Ramadan with such manners as he has been asked to, must cut himself off completely from all else so that he can observe the manners for the celebration and feast [of Allah], coming to know of the station of the Host, insofar as this is possible. According to the order of the Holy Apostle, peace be upon him and his progeny, (which is related in one of his sermons) all of the servants of God, the Supreme, have been invited by Him to a feast in the blessed month of Ramadan and are to be the guests of the Provider at His feast. He says there: "O you people! The month of Allah is approaching you ... and you have been invited in it to the feast of Allah." In this few days until the blessed month of Ramadan, you should reflect, reform yourselves, and pay attention to God Almighty, seek forgiveness for your unbecoming behavior and deeds, and if, God forbid, you have committed a sin, repent for it prior to entering the blessed month of Ramadan. Habituate your tongue to intimate devotions to God the Almighty .
God forbid that in the blessed month of Ramadan you should backbite or slander, or in short, sin, and so become polluted by transgression in the presence of the Lord, the Exalted, at His feast.
The Greatest Jihad (Combat with the Self), Text, Page: 22