I have retained in my memory these words of God's Messenger, “Leave what causes you doubt and turn to what does not cause you doubt. Truth is tranquility, but falsehood is doubt.”
Ahmad, Tirmidhi and Nasa’i transmitted it, and Darimi transmitted the first part.
Jabir reported God’s Messenger as saying, “Flesh which has grown out of what is unlawful will not enter paradise*, but hell is more fitting for all flesh which has grown out of what is unlawful.”
Ahmad, Darimi, and Baihaqi, in Shu'ab al-iman, transmitted it.
*The reference here is to people who live on unlawful source of income.
Wabisa b. Ma'bad reported God’s Messenger as saying, “Have you come to ask about righteousness and sin, Wabisa?” When he replied that he had, he joined his fingers and striking his breast with them said, “Ask yourself for a decision, ask your heart for a decision (saying it three times). Righteousness is that with which the soul is tranquil and the heart is tranquil, but sin is that which rouses suspicion in the soul and is perplexing in the breast, even if people give you a decision in its favour.”
‘Abdallah b. Mas'ud reported God’s Messenger as saying, “No man who acquires unlawful property and gives some of it in alms will have it accepted from him; neither will he receive a blessing for it if he con-tributes some of it; and if he leaves some of it behind him (i.e. when he dies) it will be his provision for hell. God does not obliterate an evil deed by an evil one, but He obliterates an evil deed by a good one. What is impure does not obliterate what is impure.”
Ahmad transmitted it, and the same is given in Sharh as-sunna.