Hadith #14 (The Forty Hadith of Imam Nawawi)
Book: The sanctity of Muslim blood; three cases permitting capital punishment
Narrator(s): Ibn Masood
Grade: Sahih

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.”

Source: https://parallelquran.com/hadith/forty-nawawi-14/