Describing the evil of murder, the Qur’an has this to say:
“Whoever killed one human being, should be looked upon as though he had killed all mankind; and whoever saved a human life should be regarded as though he had saved all mankind.” (5:32)
This has been expressly stated in the scripture because, when a man commits a crime of this nature, he breaks the tradition of respect for life. This tradition in society serves as a kind of psychological check against one man making a murderous assault on another. Once this check is removed, there is no barrier left in the way of indulging in such criminal activities. People become emboldened when such a precedent is set by a wrongdoer. That is how the murder of one man opens the door to more murders. Thus Islam holds murder to be abhorrent.