Why Noah was the first Prophet to warn of the Dajjaal
27-4-2015 | IslamWeb
Question:
assalam alikum bro I was just reading a hadith that says that every prophet after noah including noah warned his nation against the anti Christ so I was just wondereding why didn't adam warn his people about the anti Christ as well why did it only start with noah if youknow what I mean jazzzakkallah :)
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Al-ʻAyni 
underlined two points concerning this in his book ʻUmdat Al-Qaari Sharh Saheeh Al-Bukhari in his commentary on the following Hadeeth: Ibn ʻUmar 
said, “The Messenger of Allaah, sallallaahu ‘alayhi wa sallam, stood among the people and praised Allaah as He is worthy, and mentioned the Dajjaal, saying, "I warn you of him, and there has been no Prophet who has not warned his people of him. Nooh (Noah) warned his people of him. But I tell you about him a word which no Prophet had told his people; you know that he is one-eyed and Allaah is not one-eyed."” [Al-Bukhari]
Al-ʻAyni said, “His words: "Nooh warned his people". he specified Nooh after generalizing because Nooh was the first Prophet to warn his people and threaten them. Prior to him, the role of the Prophets was to offer guidance and direction to their peoples as parents to children; and because he was the first Messenger to be sent with religious ordainment; Allaah The Exalted says (what means): {He has ordained for you of religion what He enjoined upon Nooh…} [Quran 42:13]; or because he was the second father of humanity and his descendants are the ones who survived in this world (after the Great Flood) apart from any others.”
For more benefit, please refer to Fatwa 26728.
Allaah Knows best.