μή μοι θεοὺς καλοῦσα βουλεύου κακῶς· πειθαρχία γάρ ἐστι τῆς εὐπραξίας μήτηρ, γυνὴ Σωτῆρος· ὦδ᾽ ἔχει λόγος → When you invoke the gods, do not be ill-advised. For Obedience is the mother of Success, wife of Salvation—as the saying goes.
P. ἀλυσιτελῶς (Xen.), P. and V. ἀνόνητα (Plato, Republic and Euripides, Electra 507).
in vain: P. and V. μάτην, ἄλλως, διὰ κενῆς, V. ματαίως, ἄκραντα; see in vain, under vain.