In the New Testament the Greek word used for 'Lord' is often 'kurios' or 'Kyrie', a transliteration of Greek Κύριε (Kyrie), vocative case of Κύριος (Kyrios). I understand and believe the implications from the Septuagint is relating YHWH.
In Luke 5:5 Peter referred to Jesus as 'master', epistates (Ἐπιστάτα), and in 5:8 he used Kyrie (κύριε).
Luke 5:5 And Simon answered, “Master, we toiled all night and took nothing! But at your word I will let down the nets.”
epistates (Ἐπιστάτα) http://bibleapps.com/greek/1988.htm
Luke 5:8 But when Simon Peter saw it, he fell down at Jesus' knees, saying, “Depart from me, for I am a sinful man, O Lord.”
kurios. (κύριος, ου, ὁ) http://bibleapps.com/greek/2962.htm
My question is more about epistates (Ἐπιστάτα). How would that term have been routinely used during that time period? It seems that Kurios/Kyrie were used interchangeably with people of high standing so would 'epistates' have been used in the same way? I take it to be comparable to addressing a middle manager or Forman and addressing the owner of the company or boss. Relationally how would Peters address be intended and how would it have been received by a common person of the time.