"If we want the revolution to continue with the same speed, steadfastness, and in the path of Islam without wavering to the left or to the right, we have to set the goals of our nation and also of the Islamic nations around us. We have to make efforts to bring these goals to fruition and not stop trying. The greatest danger is not that we become tired or exhausted, but that we lose sight of the revolutionary goals and ideals."
January 1, 1970
https://en.wikiquote.org/wiki/Ali_Khamenei