Rashi on Genesis 43:23/רש"י על בראשית מ״ג:כ״ג

1אלהיכם YOUR GOD — your God because of your own merits: and if your own merits do not suffice, then ואלהי אביכם THE GOD OF YOUR FATHER — because of your father’s merits HE HAS GIVEN YOU A TREASURE (Genesis Rabbah 92:4).