Note : Rasulullah (Sallallaho Alaihe Wasallam) is also reported to have said : "Listen to happy tidings, and convey them to other as well, that whosoever believes in La-Ilaha-Illallah with sincerity of heart, shall enter Paradise." It is the Ikhlaas that is valued by Almighty Allah. A small deed  done with Ikhlaas (sincerity) earns a great reward; but anything done for the sake of mere show or to please some people, will earn no good reward, but punishment from Almighty Allah. That is why a person who recites the Kalimah with sincerity of heart will certainly be pardoned and admitted into Paradise. It may or may not be that he undergoes some punishment for his sins before going to Paradise; but if Almighty Allah is really pleased with particular deeds of a sinning believer, He may forgive all his sins in the very first instance. When Allah is so Merciful and Gracious, it is our greatest misfortune if we do not serve and obey Him in full. In short, great rewards are promised in these ahadith for one who believes in the Kalimah Tayyibah. Two  possibilities are however there : he may have to suffer some punishment for his sins according to the general rule before being forgiven, or he may be forgiven forthwith without any punishment by Almighty Allah, out of sheer Mercy and Grace.

Yahya bin Akhtam (Rahmatullah alaih) is a Muhaddith. After his death, somebody saw him in a dream, and asked him how he had faced. He replied : "I appeared before Almighty Allah, and He said to me : "You sinful old man, you did this and you did that', till all my sins were recounted one by one, and I was asked if I had any explanation in my defence. I submitted that no hadith to that effected had been conveyed to me. Then Allah asked : "What hadith had been conveyed to you ?' I submitted : "I was told by Abdur Razzaq who was told by Muammar who was told by Zuhri who was told by Urwah who was told by Hadhrat Aa-ishah (Radhiyallaho anha), who was told by Rasulullah (Sallallaho alaihe wasallam), who was told by Jibraa-eel (Alayhis salaam), who was told by Jibraa-eel (Alayhis salaam), who was told by You : 'A person who grows to told age in Islam may have deserved punishment on account of his sins, yet as a token of respect for his old age, I pardon him', and You know that I am very old." Allah then said, Abdur Razzaq spoke the truth, Muammar spoke the truth, Zuhri spoke the truth, Urwah spoke the truth, 'Aa-ishah (Radhiyallaho anha) spoke the truth, Rasulullah (Sallallaho alaihe wasallam) spoke the truth, Jibraa-eel (Alayhis salaam) spoke the truth, and what I had said is true.' After that, it was ordered that I should be admitted into Paradise."