Parashas Vayigash · Passuk 46:1
Yisrael set out with all that was his and came to Be’er Sheva, and he offered sacrifices to the God of his father Yitzchak.
Torah Temimah points to Bereishit Rabbah (and parallel).
TT lemma: לאלהי אביו יצחק.
English: “To the God of his father Yitzchak” — it does not say “to the God of his father Avraham.” Rabbi Yochanan said: This teaches that a person is obligated in the honor of his father more than in the honor of his father’s father.
Derash on the verse (midrash) — not a formal named middah of the 13. The omission of Avraham’s name yields a ranking of obligations.
A person is obligated to honor his own father more than he is obligated to honor his grandfather.