1 Samuel 20:18 in the World English Bible
Then Jonathan said to him, “Tomorrow is the new moon, and you will be missed, because your seat will be empty.
Context
17 And Jonathan caused David to swear again, because he loved him: for he loved him as he loved his own soul.
18 Then Jonathan said to David, To morrow is the new moon: and thou shalt be missed, because thy seat will be empty.
19 And when thou hast stayed three days, then thou shalt go down quickly, and come to the place where thou didst hide thyself when the business was in hand, and shalt remain by the stone Ezel.