It is narrated from Hazrat Anas (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: A man remains involved in such sins for a long period that if he were to die in that state, he would enter Hell. But then a change occurs in him and he becomes engaged in good deeds. In the same way, do not be amazed at any person until you see on which deed his end occurs, because sometimes a person spends his whole life or a long period in good deeds, so that if he were to die in that state, he would enter Paradise, but then a change occurs in him and he becomes involved in sins.