1 CORINTHIANS 12:28   And God hath set some in the church, first Apostles, secondarily Prophets..

EPHESIANS 4:11   And He gave some Apostles and some Prophets..

* A Prophet is one who utters a communication, in speaking the mind of God. the Old
  Testament Prophet was also called a seer and a watchman.

Old Testament Prophets

  A Seer

  2 Kings 6:8-17   Vs.12    And one of his servants said, None, my lord, O king: but
  Elisha, the prophet that is in Israel, telleth the king of Israel the words that thou speakest
  in thy bedchamber.

  A Watchman

  Ezekiel 3:16-21   Vs.17  Son of man, I have made thee a watchman unto the house of
  Israel: therefore hear the word at my mouth, and give them warning from me.
  
  * God revealed things to prophets by dreams, visions and speaks to them audibly.

New Testament Prophets

  1 Corinthians 12:28  ..And God hath set some in the church....prophets

  Ephesians 4:11  ..And he gave some...prophets

  * The scriptures makes it very plain that God has set in the church; Prophets, to believe
     otherwise is to ignore the word of God.

   Acts 13:1   Now there were in the church that was at Antioch certain prophets and
   teachers;

  Acts 11:27-28   And in these days came prophets from Jerusalem unto Antioch.
  Vs.28   And there stood up one of them named Agabus, and signified by the spirit that
  there should be great dearth throughout all the world: which came to pass in the days of
  Claudius Caesar.

  Acts 21:4,10-11   And as we tarried there many days, there came down from Judaea a
  certain prophet, named Agabus...

Prophets are Persecuted

  Luke 13:34   O Jerusalem. Jerusalem, which killest the prophets and stonest them that
  are sent to thee..

  2 Chronicles 36:16   But they mocked the messengers of God, and misused his
  prophets, until there was no remedy.

  1 Chronicles 16:22  Warning! Touch not mine anointed, and do my prophets no harm.

Prophets are not Honored
  
  Matthew 13:57   And they were offended in him. But Jesus said unto them, A prophet is
  not without honour, save in his own country, and in his own house.

  Luke 4:24   And he said, Verily I say unto you, no prophet is accepted in his own
  country.

  * Certain gifts of the Holy Spirit seem to manifest more frequently in a prophets
     ministry, then others, such as:

     Word of Knowledge
     Word of Wisdom
     Prophecy

     * Prophets are sometimes sent to leaders, such as in the case of Apostle Paul
        ( Acts 21:4, 10-11 )
  
      * Notice that Agabus only spoke, what the Holy Spirit gave him to speak.