Here is a very beneficial clip from Abu Muhammad al-Maghribee (hafidhahullah Ta'ala) about why we do not participate in Halloween or trick-or-treating!
Abu Hurairah (رضي الله عنه) narrated that the Prophet ﷺ said: "Whoever invites to guidance will be rewarded like those who follow him in the guidance are rewarded, and that will not decrease the reward of those who have followed him." [Collected by Imām Muslim]
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