1 Samuel 18:10

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.

On the morrow, that the evil spirit from God came upon Saul. This rankling thought brought on a sudden paroxysm of his mental malady.

He prophesied, х wayitnabee' (H5012)]. The term denotes one under the influence either of a good or a bad spirit. In the present instance it is used to express that Saul was in a frenzy-a violent raving (cf. 1 Samuel 19:24). [The Septuagint, mistaking the sense-has proefeeteusen, prophesied, which our translators borrowed. But it is an unhappy translation.] David, perceiving the symptoms, "played with his hand" (1 Samuel 16:23 - i:e., hastened, by the soothing effects of his harp, to allay the stormy agitation of the royal mind. But ere its mollifying influence could be felt, Saul hurled a javelin at the head of the young musician.

There was a javelin in Saul's hand. It was the royal sceptre, which he always had. Had it been followed by a fatal result, the deed would have been considered the act of an irresponsible maniac. It was repeated more than once ineffectually, and Saul became impressed with a dread of David as under the special protection of Providence.