Ibn `Umar (May Allah bepleased with them) reported:

We were talking about the Farewell Pilgrimage without knowing what was it when Messenger of Allah (ﷺ) was also present. He (ﷺ) stood up and recited the Praise and Glorification of Allah. He then gave a detailed account of Ad-Dajjal and said, 'Every Prophet (ﷺ) sent by Allah had warned his people against his mischief. Nuh (ﷺ) )warned his nation and so did all the Prophets after him. If he (i.e., Ad-Dajjal) appears among you, his condition will not remain hidden from you. Your Rubb is not one-eyed, but Ad-Dajjal is. His right eye is protruding like a swollen grape. Listen, Allah has made your blood, and your properties as inviolable as of this day of yours (i.e., the Day of Sacrifice), in this city of yours (i.e., Makkah), in this month of yours (i.e., Dhul -Hijjah). Listen, have I conveyed Allah's Message to you?'' The people replied in affirmative. There upon he said, "O Allah, bear witness.'' And he repeated it thrice. He (ﷺ) concluded: "Do not revert after me as infidels killing one another". <b>[Al-Bukhari]</b>.

وعن ابن عمر رضي الله عنهما قال‏:‏ كنا نتحدث عن حجة الوداع، والنبي صلى الله عليه وسلم بين أظهرنا، ولا ندري ما حجة الوداع، حتى حمد الله رسول الله صلى الله عليه وسلم، وأثنى عليه، ثم ذكر المسيح الدجال فأطنب في ذكره، وقال‏:‏ “ ما بعث الله من نبي إلا أنذره أمته‏:‏ أنذره نوح والنبيون من بعده، وإنه إن يخرج فيكم فما خفي عليكم من شأنه فليس يخفى عليكم، إن ربكم ليس بأعور، وإنه أعور عين اليمنى، كأن عينه عنبة طافية‏.‏ ألا إن الله حرم عليكم دماءكم وأموالكم ، كحرمة يومكم هذا، في بلدكم هذا، في شهركم هذا، ألا هل بلغت‏؟‏” قالوا‏:‏ نعم، قال‏:‏ “اللهم اشهد -ثلاثًا- ويلكم، أو ويحكم، انظروا، لا ترجعوا بعدي كفارًا يضرب بعضكم رقاب بعض‏"‏ ‏(‏‏(‏رواه البخاري ، وروي مسلم بعضه‏)‏‏)‏‏.‏