'On that Day' in the Bible

And they gathered together to Mizpah, and drew water, and poured it out before LORD, and fasted on that day, and said there, We have sinned against LORD. And Samuel judged the sons of Israel in Mizpah.

And as Samuel was offering up the burnt-offering, the Philistines drew near to battle against Israel, but LORD thundered with a great thunder on that day upon the Philistines, and discomfited them, and they were smitten down before

And the king said to Doeg, Turn thou, and fall upon the priests. And Doeg the Edomite turned, and he fell upon the priests, and he killed on that day eighty-five persons who wore a linen ephod.

And David said to Abiathar, I knew on that day, when Doeg the Edomite was there, that he would surely tell Saul. I have occasioned [the death] of all the persons of thy father's house.