Ahadith on Virtues of Kalimah Tayyabah

Certainly pardoned by Almighty Allah

The Kalimah does not let any sin remain unwashed

Note : That not deed can excel frofessing this Kalimah is quite apparent, because without belief in this Kalimah no action carries any reward. It is the pre-requisite for the acceptance of Salaat, Fasting, Hajj and Zakaat, because unless there is Imaan, no action is acceptable. Recitation of Kalimah Tayyibah, which amounts to profession of faith, is not dependent on anything else. If a person has only Imaan and no other virtue in his account, sooner or later he is bound (through the grace of Allah) to get admission into Paradise. On the other hand, if a person does not possess Imaan, then no amount of good deeds will be sufficient for his salvation.

The second part of the above-mentioned hadith is that the Kalimah does not let any sin remain unwashed. It  is unanimously agreed that if a person embraces Islam in his old age, and immediately after recitation of the Kalimah he happens to meet his death, then all his sins which he had committed as disbeliever before his declaration of Imaan are remitted. If, however recitation of the Kalimah in an earlier stage is implied, then the hadith means that the Kalimah purifies and polishes the heart, and its excessive recitation will cleanse the heart, to such an extent that he must to Taubah, which will result in the forgiveness of his sins. According to one hadith, if a person is particular to recite  La-Ilaha-Illallah before  going to sleep and after getting  up, even his wordly affairs will lead to the betterment of his life in the Hereafter, and he will be guarded against misfortune and trouble.