an English idiom which means attacking imaginary enemies, or fighting unwinnable or futile battles.
Father and daughter arguing over getting married.
Dad - "I won't allow it, do you get me?"
Daughter - "You're tilting at windmills, Phil."
"Do not bullshit thy father."
Quote made by Jenny Cavilleri in the 1970 movie Love Story, refering to what her father told her when she was going to Marry a millionair
Jenny - "He reminded me of the Eleventh Commandment."
Oliver - "Eleventh?"
Jenny - "Do not bullshit thy father."