What does 1 Samuel 19-20 really mean?

¹ And Saul spoke to Jonathan his son and to all his servants, that they should kill David.
² And Jonathan told David, “Saul my father seeks to kill you. Therefore be on your guard in the morning. Stay in a secret place and hide yourself.
³ And I will go out and stand beside my father in the field where you are, and I will speak to my father about you. And if I learn anything I will tell you.”
⁴ And Jonathan spoke well of David to Saul his father and said to him, “Let not the king sin against his servant David, because he has not sinned against you, and because his deeds have brought good to you.
⁵ For he took his life in his hand and he struck down the Philistine, and the Lord worked a great salvation for all Israel. You saw it, and rejoiced. Why then will you sin against innocent blood by killing David without cause?”
⁶ And Saul listened to the voice of Jonathan. Saul swore, “As the Lord lives, he shall not be put to death.”
⁷ And Jonathan called David, and Jonathan reported to him all these things. And Jonathan brought David to Saul, and he was in his presence as before.
⁸ And there was war again. And David went out and fought with the Philistines and struck them with a great blow, so that they fled before him.
⁹ Then a harmful spirit from the Lord came upon Saul, as he sat in his house with his spear in his hand. And David was playing the lyre.
¹⁰ And Saul sought to pin David to the wall with the spear, but he eluded Saul, so that he struck the spear into the wall. And David fled and escaped that night.
¹¹ Saul sent messengers to David’s house to watch him, that he might kill him in the morning. But Michal, David’s wife, told him, “If you do not escape with your life tonight, tomorrow you will be killed.”
¹² So Michal let David down through the window, and he fled away and escaped.
¹³ Michal took an image and laid it on the bed and put a pillow of goats’ hair at its head and covered it with the clothes.
¹⁴ And when David fled and escaped, he came to Samuel at Ramah and told him all that Saul had done to him. And he and Samuel went and lived at Naioth.
¹⁵ Then Saul sent the messengers to see David, saying, “Bring him up to me in the bed, that I may kill him.”
¹⁶ And when the messengers came in, behold, the image was in the bed, with the pillow of goats’ hair at its head.
¹⁷ And Saul said to Michal, “Why have you deceived me so and let my enemy go, so that he has escaped?” Michal answered Saul, “He said to me, ‘Let me go. Why should I kill you?’”
¹⁸ Now David fled and escaped, and he came to Samuel at Ramah and told him all that Saul had done to him. And he and Samuel went and lived at Naioth.
¹⁹ And it was told Saul, “Behold, David is at Naioth in Ramah.”
²⁰ Then Saul sent messengers to take David, and when they saw the company of the prophets prophesying, and Samuel standing as head over them, the Spirit of God came upon the messengers of Saul, and they also prophesied.
²¹ And when it was told Saul, he sent other messengers, and they also prophesied. And Saul sent messengers again the third time, and they also prophesied.
²² Then he himself went to Ramah and came to the great well that is in Secu. And he asked, “Where are Samuel and David?” And one said, “Behold, they are at Naioth in Ramah.”
²³ And he went there to Naioth in Ramah. And the Spirit of God came upon him also, and as he went he prophesied until he came to Naioth in Ramah.
²⁴ And he too stripped off his clothes, and he too prophesied before Samuel and lay naked all that day and all that night. Thus it is said, “Is Saul also among the prophets?”
¹ Then David fled from Naioth in Ramah and came and said before Jonathan, “What have I done? What is my guilt? And what is my sin before your father, that he seeks my life?”
² he said to him, “Far be it from you! You shall not die. Behold, my father does nothing either great or small without disclosing it to me. And why should my father hide this from me? It is not so.”
³ Then David took an oath again, and said, “Your father knows well that I have found favor in your eyes, and he thinks, ‘Do not let Jonathan know this, lest he be grieved.’ But truly, as the Lord lives and as your soul lives, there is but a step between me and death.”
⁴ Then Jonathan said to David, “Whatever you say, I will do for you.”
⁵ David said to Jonathan, “Behold, tomorrow is the new moon, and I should not fail to sit at table with the king. But let me go, that I may hide myself in the field till the third day at evening.
⁶ If your father misses me at all, then say, ‘David earnestly asked leave of me to run to Bethlehem his city, for there is a yearly sacrifice there for all the clan.’
⁷ If he says, ‘Good!’ it will be well with your servant, but if he is angry, then know that harm is determined by him.
⁸ Therefore deal kindly with your servant, for you have brought your servant into a covenant of the Lord with you. But if there is guilt in me, kill me yourself, for why should you bring me to your father?”
⁹ And Jonathan said, “Far be it from you! If I knew that it was determined by my father that harm should come to you, would I not tell you?”
¹⁰ Then David said to Jonathan, “Who will tell me if your father answers you roughly?”
¹¹ Jonathan said to David, “Come, let us go out into the field.” So they both went out into the field.
¹² And Jonathan said to David, “The Lord, the God of Israel, be witness! When I have sounded out my father, about this time tomorrow, or the third day, behold, if he is well disposed toward David, shall I not then send and disclose it to you?
¹³ But should it please my father to do you harm, the Lord do so to Jonathan and more also if I do not disclose it to you and send you away, that you may go in safety. May the Lord be with you, as he has been with my father.
¹⁴ If I am still alive, show me the steadfast love of the Lord, that I may not die;
¹⁵ but do not cut off your steadfast love from my house forever, when the Lord cuts off every one of the enemies of David from the face of the earth.
¹⁶ So Jonathan made a covenant with the house of David, saying, “May the Lord take vengeance on David’s enemies.”
¹⁷ And Jonathan made David swear again by his love for him, for he loved him as he loved his own soul.
¹⁸ Then Jonathan said to David, “Tomorrow is the new moon, and you will be missed, because your seat will be empty.
¹⁹ And on the third day I will shoot three arrows to the side of it, as though I shot at a mark.
²⁰ I will shoot three arrows to the side of it, as though I shot at a mark.
²¹ And behold, I will send the boy, saying, ‘Go, find the arrows.’ If I say to the boy, ‘Look, the arrows are on this side of you, take them,’ then you are to come, for, as the Lord lives, it is safe for you and there is no danger.
²² But if I say to the youth, ‘Look, the arrows are beyond you,’ then go, for the Lord has sent you away.
²³ And as for the matter of which you and I have spoken, behold, the Lord is between you and me forever.”
²⁴ So David hid himself in the field. And when the new moon came, the king sat down to eat food.
²⁵ And the king sat on his seat, as at other times, on the seat by the wall. Jonathan sat opposite, and Abner sat by Saul’s side, but David’s place was empty.
²⁶ Nevertheless, Saul did not say anything that day, for he thought, “Something has happened to him. He is not clean; surely he is not clean.”
²⁷ But on the second day, the day after the new moon, David’s place was empty. And Saul said to Jonathan his son, “Why has not the son of Jesse come to the meal, either yesterday or today?”
²⁸ Then Jonathan answered Saul, “David earnestly asked leave of me to go to Bethlehem.
²⁹ He said, ‘Let me go, for our clan holds a sacrifice in the city, and my brother has commanded me to be there. So now, if I have found favor in your eyes, let me get away and see my brothers.’ For this reason he has not come to the king’s table.”
³⁰ Then Saul’s anger was kindled against Jonathan, and he said to him, “You son of a perverse, rebellious woman, do I not know that you have chosen the son of Jesse to your own shame, and to the shame of your mother’s nakedness?
³¹ For as long as the son of Jesse lives on the earth, neither you nor your kingdom shall be established. Therefore send and bring him to me, for he shall surely die.”
³² And Jonathan answered Saul his father, “Why should he be put to death? What has he done?”
³³ But Saul hurled his spear at him to strike him. So Jonathan knew that his father was determined to put David to death.
³⁴ Jonathan rose from the table in fierce anger and ate no food the second day of the month, for he was grieved for David, because his father had disgraced him.
³⁵ In the morning Jonathan went out into the field to the appointment with David, and with him a little boy.
³⁶ And he said to his servant, “Run, find the arrows that I shoot.” As the boy ran, he shot an arrow beyond him.
³⁷ And when the boy had come to the place of the arrow that Jonathan had shot, Jonathan called after the boy and said, “Is not the arrow beyond you?”
³⁸ And Jonathan called after the boy, “Hurry! Be quick! Do not stay!” So Jonathan’s boy gathered up the arrows and came to his master.
³⁹ But the boy knew nothing. Only Jonathan and David knew the matter.
⁴⁰ Then Jonathan gave his weapons to his boy and said to him, “Go and carry them to the city.”
⁴¹ And as soon as the boy had gone, David rose from beside the stone heap and fell on his face to the ground and bowed three times. And they kissed one another and wept with one another, David weeping the most.
⁴² Then Jonathan said to David, “Go in peace, because we have sworn both of us in the name of the Lord, saying, ‘The Lord shall be between me and you, and between my offspring and your offspring, forever.’” And he rose and departed, and Jonathan went into the city.