CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 2318–2321

2318 "In [God's] hand is the life of every living thing and the breath of all mankind" (Job 12:10).
2319 Every human life, from the moment of conception until death, is sacred because the human person has been willed for its own sake in the image and likeness of the living and holy God.
2320 The murder of a human being is gravely contrary to the dignity of the person and the holiness of the Creator.
2321 The prohibition of murder does not abrogate the right to render an unjust aggressor unable to inflict harm. Legitimate defense is a grave duty for whoever is responsible for the lives of others or the common good.