(10) باب حُسْنِ إِسْلاَمِ الْمَرْءِ
It was narrated that Abu Sa'eed Al-Khudri said:
"The Messenger of Allah [SAW] said: 'If a person accepts Islam, such that his Islam is good, Allah will decree reward for every good deed that he did before, and every bad deed that he did before will be erased. Then after that will come the reckoning; each good deed will be rewarded ten times up to seven hundred times. And each bad deed will be recorded as it is, unless Allah, the Mighty and Sublime, forgives it.'"
Reference: Sunan an-Nasa'i 4998
In-book reference: Book 47, Hadith 14
English translation: Vol. 6, Book 47, Hadith 5001