1 Samuel 18:10

Overview - 1 Samuel 18
Jonathan loves David.
Saul envies his praise;
10 seeks to kill him in his fury;
12 fears him for his good success;
17 offers him his daughters for a snare.
23 David persuaded to be the king's son-in-law, gives two hundred foreskins of the Philistines for Michal's dowry.
28 Saul's hatred and David's glory increase.
Treasury of Scripture Knowledge

1 Samuel 18:10  (King James Version)
And it came to pass on the morrow, that the evil spirit from God came upon Saul, and he prophesied in the midst of the house: and David played with his hand, as at other times: and there was a javelin in Saul's hand.

the evil spirit
1 Samuel 16:14 1 Samuel 16:15 19:9 26:19

and he prophesied
{Wyyithnabbai,} rather, "and he pretended to prophesy; for the verb is in {Hithpal,} the signification of which conjugation is not only reflex action, but also affectation of the action: Jeremiah 29:26 ,27. The meaning seems to be, that Saul, influenced by the evil spirit, feigned to be prophesying, the better to conceal his murderous intentions, and to render David unsuspicious.
19:24 1 Kings 18:29 ; 1 Kings 22:12 1 Kings 22:20-23 Jeremiah 28:2-4 Jeremiah 28:11 ; Zechariah 13:2-5 ; Acts 16:16
2 Thessalonians 2:11

1 Samuel 16:16 1 Samuel 16:23

and there was
{Wehachanith beyad Shool,} rather, "and the javelin was in the hand of Saul;" for the javelin or spear was the emblem of regal authority; and kings had it always in their hand, as may be seen represented on ancient monuments. In ancient times, says Justin, kings used a spear instead of a sceptre.