What is the authenticity of Sufyan's saying, may Allah have mercy on him, which Al-Tirmidhi narrated from him: "The suspicion for which one is sinful is that which he speaks, but if he does not speak, he is not sinful"? And what is meant by it, and what is the suspicion for which a person is sinful?

Al-Nawawi prohibited evil suspicion, stating that what is forbidden is that which settles in the heart, not merely a fleeting thought. He quoted Al-Qadi as saying that the suspicion for which one is sinful is that which is spoken.

Ibn Muflih mentioned that having good suspicion of religious people is good, and that indulging in and verifying evil suspicion is impermissible.

Al-Tirmidhi narrated from Sufyan that the suspicion for which one is sinful is that which is spoken. Some scholars held that one is sinful by the suspicion itself, even if not uttered.

Ibn al-Jawzi stated that evil suspicion of Allah is forbidden, and that good suspicion of Him is obligatory. Similarly, evil suspicion of a Muslim whose outward appearance is righteous is forbidden.

He also mentioned that some suspicion is commanded, such as the testimony of a just witness, and some is permissible, such as one who doubts in their prayer.

It was narrated from Abu Hurairah, elevated to the Prophet (PBUH): "If you suspect, do not verify." The recommended suspicion is good suspicion of a Muslim brother.

Al-Baghawi mentioned that the intent of the verse is "evil suspicion." Al-Qurtubi narrated from most scholars that suspecting evil of someone whose outward appearance is good is impermissible, and that there is no harm in suspecting evil of someone whose outward appearance is evil.

Al-Bukhari said in his Sahih: "Chapter: What kind of suspicion is sinful." It was narrated from Aisha that the Prophet (PBUH) said: "I do not think so-and-so and so-and-so know anything of our religion." Al-Layth bin Sa'd said: "They were two men from the hypocrites."