An-Nawawi's 40 Hadith 14
الأربعون النووية#14Not gradedOn the authority of Ibn Masood (may Allah be pleased with him) who said: The Messenger of Allah (peace and blessings of Allah be upon him) said, “It is not permissible to spill the blood of a Muslim except in three [instances]: the married person who commits adultery, a life for a life, and the one who forsakes his religion and separates from the community.” [Al-Bukhari] [Muslim]
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Our source carries no per-scholar grade for this narration. Please verify on Sunnah.com or with a qualified scholar before relying on it.
In-book reference: 1:14