The Kav Hayashar tells us that Rashi authored a sefer in honor of a baal habayis. While he was in exile from France, he was hosted by a wealthy person. This parnes (provider) insisted and pleaded with him to stay in his home and study Torah. Due to this, Rashi authored a sefer, which was named after this wealthy benefactor.Rashi’s intent was to elevate and honor others who do kindness. By naming the sefer after the benefactor, Rashi had in mind to encourage others to do chessed as well.

Rashis Host