Why does Allah lead astray whomever He wills and guide whomever He wills, as stated in the verse: "And We did not send any messenger except with the language of his people to make clear to them. Then Allah leads astray whom He wills and guides whom He wills. And He is the Exalted in Might, the Wise"?

A detailed explanation of the issue of guidance and misguidance was previously mentioned in Fatwa (definition) no. 139442. It is recommended to refer to Chapter 21 of Ibn al-Qayyim's book "Shifa' al-Alil" concerning the purification of divine decree from evil, and to review Fatwa no. 119470 for further benefit. It is important to pay attention to the necessity of engaging in knowledge and following it with action, as it is the best way to remove obsessions and doubts. Fatwa no. 144165 can be consulted in this regard.