19On the third day go down quickly to the place where you hid yourself when the matter was in hand, and remain beside the stone heap.
Most likely Jonathan was referring to the place where David hid previously in order to listen and observe Jonathan's conversation with Saul (see 1 Samuel 19:1–7).
19 On the third day go down quickly to the place where you hid yourself when the matter was in hand, and remain beside the stone heap.