Vayhi 

ויהי

In order to prevent acrimony and rancor, the brothers misrepresented the truth and told Joseph that their father requested that he forgive them. The Sages learn from this episode the importance of peace. 

Great is peace, as even Joseph’s brothers spoke false matters in order to establish peace between Joseph and the tribes. That is what is written: “They instructed to tell Joseph, saying: Your father instructed before his death, saying: So say to Joseph: Please, forgive the transgression of your brothers and their sin, as they did evil to you” (Genesis 50:16–17). Where did Jacob command them to convey this message to Joseph? We do not find that he issued such a command.<footnote data-num="101"/> The verse then states: “Joseph wept as they spoke to him” (50:17). He said: Do my brothers suspect me of taking revenge?  “He comforted them and spoke to their heart” (50:21). The verse teaches that Joseph spoke to them persuasively. He told them: If ten lights [i.e., the ten of you] were unable to extinguish one light [i.e., me], how can one light extinguish ten lights? <source>(<i>Tanĥuma</i>, <i>Vayhi</i>) </source>