Mukhtasar Bukhari

Sayyiduna Wathilah bin Al-Asqa’ (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings of Allah be upon him) said: “The greatest slander (and most severe lie) is that a man claims someone other than his father as his father, or says he saw in a dream what his eyes did not see, or attributes to the Messenger of Allah (peace and blessings of Allah be upon him) something which he did not say.”