TT #54 · Parashas Vayeishev · Passuk 39:5
And from the time that the Egyptian put him in charge of his household and of all that he owned, Hashem blessed his house for Yosef’s sake, so that the blessing of Hashem was upon everything that he owned, in the house and outside.
Torah Temimah points to Berachos 42a (Abaye).
Sefaria — Berachos 42a (Abaye)
“Because of Yosef” — Abaye said: immediately after [hosting] Torah scholars comes blessing, as it is stated: “And Hashem blessed the Egyptian’s house because of Yosef.”
Derash on the verse (Bavli sugya) — not a formal named middah of the 13. Narrative blessing is generalized to hospitality toward scholars.
One who hosts Torah scholars draws blessing upon the house, as Potiphar’s house was blessed because of Yosef.