An ox knows its owner, and a donkey its master's crib/ "the ox knows his owner and the ass his master's crib"
By extension: a person knows who they depend on and who cares for and provides for their needs (just as even an ox and a donkey know this).
("An ox knows its owner, and a donkey its master's crib; but Israel does not know, my people do not understand" - Isaiah 1:3)
Translation
Expression (Hebrew)
יָדַע שׁוֹר קֹנֵהוּ וַחֲמוֹר אֵבוּס בְּעָלָיו
Definition (Hebrew)
בְּהַשְׁאָלָה: אָדָם יוֹדֵעַ בְּמִי הוּא תָּלוּי וּמִי דּוֹאֵג לוֹ וּמְסַפֵּק לוֹ אֶת צְרָכָיו (כְּמוֹ שֶׁאֲפִילּוּ הַשּׁוֹר וְהַחֲמוֹר יוֹדְעִים זֹאת).
("יָדַע שׁוֹר קֹנֵהוּ וַחֲמוֹר אֵבוּס בְּעָלָיו, יִשְׂרָאֵל לֹא יָדַע עַמִּי לֹא הִתְבּוֹנָן"- יְשַׁעְיָהוּ א ג)