Thayer's Greek Lexicon

 1. a herdsman, esp. a shepherd
  1) in the parable, he to whose care and control others have
committed themselves, and whose precepts they follow
2. metaph.
  1) the presiding officer, manager, director, of any assembly:
so of Christ the Head of the church
2a1. of the overseers of the Christian assemblies
2a2. of kings and princes

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The tasks of a Near Eastern shepherd were:
- to watch for enemies trying to attack the sheep
- to defend the sheep from attackers
- to heal the wounded and sick sheep
- to find and save lost or trapped sheep
- to love them, sharing their lives and so earning their trust.

During World War II, a shepherd was a pilot who guided another pilot
whose plane was partially disabled back to the base or carrier by
flying alongside him to maintain visual contact.