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Editing Authority..Ultimately all authority comes from God. God may delegated His authority to a ruler of a nation or country, or the head of a tribe, or just a father in charge of a family, however all authority are answerable to God too.

• We may label those “undesirables” as gangster chief, warlords, bandit chief or pirate captain etc, however every authority will have followers whose only submission to their authority - control is a matters of life, as well as in some cases with death.
  

God allows them to exists because just like all people have their own choice. It is matter of rule and order so that evitable each becomes a cultural entity or civilisation. When different authorities conflicts over territorial control or conflicting interests, then it may escalate into tribal wars or international conflicts.

[edit] Church authority

Church authority just as every good form of government should honour God, however when corruption set in, the authority always will die out..