According to the ancient custom, Ge 38, and the express law of God, Deuteronomy 25:5, which doubtless she had acquainted them with before, among other branches of the Jewish religion, wherein she did instruct them.
Related Commentaries of Ruth 1:11
Ruth 1:11
11 And Naomi said, Turn again, my daughters: why will ye go with me? are there yet any more sons in my womb, that they may be your husbands?