Commentary for Genesis 41:52

בארץ עניי, in the land which for me was first a land of poverty, oppression, mental anguish, and has now become the land in which my potential has come to fruition where G’d has granted me children, wealth and great honour.

For God has made me forget. Yoseif gave them names that would remind him of his former poverty so that he would never cease to be grateful.

קרא אפרים, “he called Ephrayim.” This was a reminder of the two founding fathers of the Jewish people, Avraham and Yitzchok, both of whom had described themselves as ashes, אפר. Compare Genesis 18,27 and Yitzchok, who when bound on the altar on Mount Moriah, considered himself as soon being burned to ashes. This is why the entire Jewish nation is on occasion called אפרים, compare Jeremiah 31,19: הבן יקיר לי אפרים, “truly, Ephrayim is a dear son to Me.”(G–d speaking)