Is the blood of those who insult the Prophet Muhammad and Lady Aisha lawful for Muslims to shed?

Summary

Insulting the Prophet Muhammad is a very serious matter and a grave sin. However, the fatwa does not treat the insult as grounds for individual Muslims to take matters into their own hands or use violence. Legal action, including ta'zir punishment meant to discipline the offender and society, is the right of the ruling authority, so the matter should be left to the authorities under the law. The authorities should also act wisely, convey the true facts about the Prophet, remove doubts about his character, and weigh the consequences of each approach (fiqh al-ma'al).

Written in our own words from the original fatwa — check the source before acting on it.