“Surat Al-Kahf and protection from Ad-Dajjal: The Prophet (sal Allahu alaihi wa sallam) said, “Whoever commits to memory the first ten Ayat of the Surat Al-Kahf (18), will be protected from (the trial of) Ad-Dajjal (Antichrist).” [Sahih Muslim]

In another narration, “(Whoever commits to memory) the last ten Ayat of Surat Al-Kahf, he will be protected from (the trial of) Ad-Dajjal.””