From pro (before/forth) + phēmi (to speak) — one who speaks forth God's message, and sometimes foretells future events. A prophētēs is God's authorized spokesperson, declaring His word to the people. Prophets were the conscience of Israel and the foundation of the church.
The OT prophets pointed forward to Christ: 'All the prophets testify about him' (Acts 10:43). Jesus is 'the prophet like Moses' (Deuteronomy 18:15/Acts 3:22). The church is built on 'the foundation of the apostles and prophets' (Ephesians 2:20). NT prophecy continues as a Spirit-gift (1 Corinthians 12:10) but is tested against apostolic teaching. The prophetic tradition insists: God speaks, and His people must listen.