So, there is a difference between killing and murder in the Bible ...
Exodus 20 says not to commit murder (trə·ṣāḥ), but Ecclesiastes 3 says:
"To every thing there is a season, and a time to every purpose under the heaven:
A time to be born, and a time to die; a time to plant, and a time to pluck up that which is planted;
A time to kill (la·hă·rōḡ), and a time to heal; a time to break down, and a time to build up"
So, DO NOT COMMIT MURDER, but use lethal force only when necessary to protect your family, God's covenant, or you.
From Is it sinful to kill in self-defense?...
Sorry this response took so long - can only deal with reading about the collapse of the USA about every other day.