True prophets live holy life (2Kings 4:9)
They operate under the influence of the Holy Spirit (Luke 1:67).
Sometimes they speak in parables or by signs (2Samuel 12:1-6).
A true prophet is faithful to the word received from God (Jeremiah 23:28; Ezekiel 3:17-21).
They are not after material benefits associated with the office but rather seek to do God's will (2kings 5-15-16).