1 Samuel 20:6

If thy father at all miss me, then say, David earnestly asked leave of me that he might run to Beth–lehem his city: for there is a yearly sacrifice there for all the family.

Cross-reference

In 1 Samuel 20:5, David reveals his actual plan to hide in the field — the cover story in verse 6 is a fabrication to explain his absence.

In 1 Samuel 20:28, Jonathan repeats David's exact excuse to Saul — fulfilling the instruction given here.

In 1 Samuel 16:2-5, Samuel uses a sacrifice as a cover to go to Bethlehem to anoint David — the same ruse David employs here.

1 Samuel 17:58 Historical context

1 Samuel 17:58 identifies David as from Bethlehem—supporting the cover story in 20:6 about a family sacrifice there.