Rav Gluck explains that וישב stands for ויבטחו בך יודעי שמך because the only way to pass a test is to believe in ה׳. Similarly, Rav Simcha Bunim of Pshischa says that the פסוק of ״ויהי ה׳ עם יוסף ויהי איש מצליח״ means that ה׳ was with יוסף because he was always thinking of ה׳ even when he was a successful person. A similar idea on believing in the goodness of Hashem: Rav Shternbach explains that the reason why there were good smells in the wagons of the buyers of יוסף was to show יוסף that even though it might look bad at the moment but really it’s all for the good.
The רל״ג explains that יעקב gave יוסף the כתונת פסים with many different colors to show that even though there are many different Jews we all need to be part of the same כתונת.
The Kotzker Rebbe explains that the פסוק of ״וישאלהו האיש לאמר מה תבקש״ was said by the מלאך גבריאל to יוסף and is meant to teach us that each one of us needs to ask ourselves what are our goals and aspirations?
In describing how יוסף responds to his father’s request to go find his brothers the פסוק says ״ויאמר לו הנני״ and the אגרא דכלתא says that this teaches us that really he didn’t want to go but he was going because of ״לו״ because his father had asked him. Similarly, Reb Elya Svei explains that יוסף really saw the vision of what his father thought he should be and that made him feel that he could not let his father down. Another example of kibud av: Rav Moshe Feinstein says that יוסף went down to שכם even though he knew that they might hurt him because שלוחי מצוה אינן ניזוקין and he was doing the מצוה of כיבוד אב ואם.
The מדרש explains that had ראובן known that his actions would be written in the תורה he would’ve saved יוסף by carrying him on his own back to his father. Does that mean that he was haughty? Rav Shternbach explains that it means that he would’ve done that not for גאוה but rather to teach the Jewish people how far we must go to save another Jew. A related thought on Gaava elsewhere in the parsha: Rav Moshe Schor explains that the stars and moon represent רוחניות. So יוסף thought יעקב would be proud of him, but really יעקב told him not to show off his רוחניות.
Why did יעקב send the יוסף to his brothers if he knew that they hated him? Rav Shternbach gives two answers. His first answer is that יעקב was 100% sure that the brothers being in שכם was bad, and we know אין ספק מוציא מידי ודאי, so the chance that they would hurt יוסף doesn’t overrule the 100% chance that שכם is bad for them. His second answer is that יעקב thought that when the brothers see that יוסף is coming to help them they would see how much he really loved them and they wouldn’t hurt him.
Rav Yonason Eibshitz explains that ולא יכלו דברו לשלום is telling us that most times hatred can go away when the two parties speak peacefully. Another vart on the word Shalom in the parsha elsewhere: Rav Simcha Bunim of Pshischa says that יעקב told יוסף to see how his brothers are doing with the world “שלום” because that word can also mean completeness and he was telling יוסף to see how great his brothers were.