Is the layman sinful who imitates someone he believes to be trustworthy and knowledgeable, while in reality that person is ignorant and has come forward to issue fatwas and speak about Allah without right, and does that result in the layman's negligence in his religion or his condoning of killing and declaring others disbelievers?

In matters of Islamic law, a distinction must be made between what is clear and what is ambiguous, and the implications that arise from each. Major issues, such as those concerning lives and honors, should only be ruled upon by those deeply rooted in knowledge. If an ordinary person (layman) exerts effort in seeking the truth and consults those qualified to issue fatwas, then they are excused, based on the hadith: "Whoever gives a fatwa without knowledge, their sin is upon the one who gave them the fatwa." Furthermore, there is a consensus among scholars that the general populace is obliged to follow their scholars in matters they are ignorant of.