Lech Lecha
The Gemara brings a story with Nachum Ish Gam Zu who would say “whatever happens is for the good.” One time the Yidden wanted to send a present to the king. They chose Nachum to be the one since he was used to having nissim happen. They sent a chest full of precious stones and pearls with Nachum to bring to the king. On the way he stopped at an inn and slept there overnight. The innkeepers stole the treasures and filled the chest with dirt. When Nachum reached the palace the officers of the king opened the chest and saw it filled with dirt. The king wanted to kill him because he claimed the Yidden were mocking him. Nachum said “gam zu l’tova.” Eliyahu HaNavi appeared as one of the officers of the king and said, “This is the dirt of Avraham Avinu. When Avraham threw dirt it would turn into swords and when he threw straw it would turn into arrows.” Rashi explains this happened when Avraham fought with the king in this parsha. As the passuk says in our haftara “יתן כעפר חרבו כקש נדף קשתו.” The king decided that they would test out the dirt in a battle against a province which he couldn’t conquer. The soldiers used the dirt which turned into swords and they captured the province. Nachum was brought to the king’s treasure house and the servants filled up his chest with precious stones and pearls and sent him back with great honor.
The Ben Yehoyada explains Nachum was rewarded twice in the place of bad. For the bad that they took his treasures, the king filled up the chest with treasures which he took back with him. For trying to kill him, the king sent warriors to escort him home.
On Nachum’s return journey he slept in the same inn. The innkeepers asked him, “What did you bring with you that they gave you so much honor?” He answered, “What I took from here, I brought there.” The innkeepers knocked down their house and brought dirt to the king. They said “The dirt which was brought by Nachum is ours.” The king’s officers tested the dirt and nothing happened. The innkeepers were taken out and killed.
Rashi explains the passuk יתן כעפר חרבו כקש נדף קשתו that Avraham destroyed nations and kings by using his sword to make corpses as numerous as dirt. With his bow (קשת) he killed many like straw is blown down like the wind(קש).
The Radak explains although Avraham fought with just 318 men, they won because of Avraham’s bitachon in Hashem. The words in this passuk are a future lashon, while at the same time referring to Avraham Avinu in the past. This is to teach us that as Hashem did with Avraham Avinu, He will do with each and every tzaddik that will have ahavas Hashem as Avraham.