C. F. Keil and Franz Delitzsch on 1 Samuel 13:8

1Sa 13:8 Saul’s untimely sacrifice. - 1Sa 13:8, 1Sa 13:9. Saul waited seven days for Samuel’s coming, according to the time appointed by Samuel (see at 1Sa 10:8), before proceeding to offer the sacrifices through which the help of the Lord was to be secured for the approaching campaign (see 1Sa 13:12); and as Samuel did not come, the people began to disperse and leave him. The Kethib וייחל is either the Niphal ויּיּחל, as in Gen 8:12, or Piel וייחל; and the Keri ויּוחל (Hiphil) is unnecessary. The verb יעד may easily be supplied to שׁמוּאל אשׁר from the word למּועד (see Ges. Lehrgeb. p. 851).