ξένῳ δὲ σιγᾶν κρεῖττον ἢ κεκραγέναι → it's better for a stranger to keep silence than to shout (Menander)
impious: P. and V. ἄθεος, ἀσεβής, δυσσεβής (rare P.), V. δύσθεος.
shameless: P. and V. ἀναιδής, P. ὑβριστικός.