Commentary for I Samuel 20:19

For three days. You shall triple the days, and then you should go down very much, i.e., when the third day arrives,¹⁴Others translate וְשִׁלַשְׁתָּ as “mark three times” [the spot where to hide] to avoid any misunderstanding. The same expression [וְשִׁלַשְׁתָּ], is used to tell the Bnei Yisroel to mark the borders of the land into three parts in Devarim 19:3. you should go down into a secret place, and hide very well, because they will seek you then. And you shall come to this secret place, where you are hiding today, which is a work day.¹⁵I.e., the day after Rosh Chodesh is described as a work day in comparison to Rosh Chodesh which is considered a holiday because they did not engage in their usual work. And similarly Targum Yonoson renders, on a week day, for he hid on that day, as it is stated, 'and Dovid hid in the field,'¹⁶Below verse 24. and immediately, 'it was the New Moon'¹⁷Ibid. on the next day.

The marker stone. A stone which was a landmark for travelers.¹⁸הׇאָזֶל meaning “[a stone for] those who go.” Others, maintain that the marker stone was used as a target at which arrows were shot.

The marker for those who travel. And similarly Targum Yonoson renders אֶבֶן אָתָא, 'the stone [that served as] a sign.'¹⁹For travelers.