It is not clear exactly how Saul's attendants came to this knowledge. Most likely, seeing his suffering, they realized that there must be some problem in his relationship with the Lord. Living under the terms of the old covenant, they would have understood curses to be a sign of God’s displeasure (see Deuteronomy 28:1–68).
15 And Saul’s servants said to him, “Behold now, a harmful spirit from God is tormenting you.