Hadith related by Ibn Majah quotes the Prophet as saying: "What is credited to a believer of his action and good deed after his death is any useful knowledge he might have taught or spread, a God-fearing child he might have left behind, a copy of the Qur'an he might have left to an heir, a mosque he might have built, a house he might have dedicated for use by travelers, a stream or river he might have caused to run, a donation to charity (i.e. sadaqah) he might have set aside when he was enjoying good health. All that catches up with him after his death." Another authentic Hadith related by Muslim quotes the Prophet as saying: "Any Muslim who initiates a good practice receives its reward and the reward of anyone who follows his example without reducing their reward by the smallest of fractions, and any Muslim who initiates a bad practice will bear its burden as well as the burden of everyone who follows his example without reducing their burdens in anyway."
