Musar zu Jirmejahu 29:11

Surveillance over the needs of others: It is also from the way of Wisdom for It to be surveying all things in existence, since It is the Thought that thinks about all things in existence. And about It is it stated (Isaiah 55:8), "For My thoughts are not your thoughts"; and written (II Samuel 14:14), "and He thinks thoughts that one banished not be banished from Him"; and [also] written (Jeremiah 29:11), "For I have known the thoughts that I am thinking about you, House of Israel; thoughts of peace, and not of evil, to give to you an ending of hope." So [too,] must a person's eyes be open over the behavior of the people of God, to benefit them. And his thoughts [should] be to bring close the banished, and to think good thoughts about them. [Just] like the Mind thinks [about the] benefit of all existence, so [should] he think about the benefit of his fellows and counsel them [with] advice [that is] good with God and with His people, [both] individually and generally. And he [should] lead one who leaves good behavior, towards straight behavior; and he [should] be like a mind and thought to steer him and lead him to good and straight action - [just] like the Highest Thought straightens the Highest Man (the Divine Emanations below It).

Bereshit Rabbah 85, 1, commenting on Genesis 38, 1, the episode introducing Yehudah's marriage, etc., quotes Rabbi Shmuel bar Nachman who interprets Jeremiah 29,11 in which G–d is on record that all His intentions are for the good of the Jewish people, even though it may not always appear thus to us. G–d also stresses that He is fully aware of our thoughts. The sale of Joseph is an example of how what appear to be plans and actions contrary to G–d's intentions are nonetheless furthering His plans. The brothers were concerned only with ridding themselves of Joseph and the danger they thought he represented to them. Joseph and Reuben, as well as Jacob, were each mourning their part in the fate that had befallen the other; Yehudah was busy choosing a wife. G–d, on the other hand, was busy paving the way for the eventual arrival of the Messiah.