EXOD343 When someone sends us on a mission, we should report back afterward. Rashi cites the Mechilta: "Why was it necessary for Moshe to report back to God, the omniscient? Because the Torah comes to teach you derech eretz (proper behavior) from Moshe; Moshe did not say: 'Since He who sent me knows anyhow, I do not need to report.'" Rabbi Simcha Zissel Ziv cited this verse in a letter he wrote to someone who had neglected to respond to a letter that he had previously written him, and added: "We must learn derech eretz from Moshe and remember to report back to someone who sends us on an errand or mission." (Chochmah Umussar, vol. 1, p. 45).