Bible Notes Online - 1-Samuel 20 - ESV
Commentary

v1-4: David's friendship with Jonathan; they were able to share their fears. Jonathan was party to Saul's plans, even those to kill David, and he felt that that information would help David, but David was concerned that Saul would keep such plans from Jonathan.

David grew discouraged, thinking that he was close to death and forgetting God’s promises to him. Jonathan responded by promising to do anything David needed.

v5-10: David was concerned to find out Saul's plans against him. Although he would be expected at Saul's table, he could not go there for fear of his life. His scheme did involve a lie, that he would return to Bethlehem, but these were desperate times for David.

v11: The beginning of their conversation was in the city, possibly Gibeah. This could therefore be overheard. They therefore went out into the field.

v12-17: Jonathan confirmed his promise to report any news to David. He knew that David would become king. As incoming king, David would be expected to kill the whole family of Saul, so Jonathan asked him to preserve all who were of his own line, see also 24.20-21.

The two re-affirmed their love for each other. This was a real and deep friendship.

v18-23: Jonathan thought of the sign of the arrows. A soldier might be expected to practice shooting, so it would not be strange for Jonathan to go out with his bow and arrows, and a servant to fetch the arrows. This provided an opportunity for Jonathan to give a sign to David without needing to be seen speaking to him.

v24-26: At the first day of the feast, Saul's thought was that David was unclean, bringing an inferred criticism of David.

v27: Saul did not even use David's name.Such was his hatred towards David.

v28-29: Jonathan lied to protect David, as agreed in v5-6, but the root problem was Saul's anger.

v30-31: Saul then showed his anger towards Jonathan, "You son of a perverse and rebellious woman!"; these were terrible words of shame towards his own son. He tried to create enmity between Jonathan and David.

v32-34: Saul's anger led to him trying to kill Jonathan. Jonathan's attempt to reason with his father was fruitless.

v35-40: Jonathan was able to use the arrangement with David, by firing arrows. The servant boy who collected the arrows was kept ignorant of the arrangement.

v41-42: David and Jonathan had a brief opportunity to speak, and bless each other. From this time there was very little contact between them.