ἃ χρὴ ποιεῖν

From LSJ

Ἰσχυρὸν ὄχλος ἐστίν, οὐκ ἔχει δὲ νοῦν → Plebs nempe res est valida, sed mentis carens → Des Volkes Masse hat zwar Macht, doch fehlt Vernunft

Menander, Monostichoi, 265

Greek > English (Woodhouse)

do what is due, to do what is due

Spanish

hacer lo que se debe