Questions about the sixth commandment?

Yahweh established the death penalty to execute severe law breakers amongst His people to help maintain law and order amongst His people. So execution is not committing murder. A thief killing someone to steal from them amongst his own people is committing murder which if caught is executed. Also soldiers in Yahweh's military who kill the enemy during wars is not murder in Yahweh's eyes but justified killings of the enemy, which Yahweh has done Himself in the past. Yahweh's death penalty law was to remove the violent individual from society and also scare the rest of the people to not commit murder amongst their own people.