θυηπολεῖται δ' ἄστυ μάντεων ὕπο τροπαῖα τ' ἐχθρῶν καὶ πόλει σωτήρια

From LSJ

ῥᾷον ὀμνύναι κἀπιορκεῖν ἢ ὁτιοῦν → they thought less of swearing and perjuring themselves than of anything else in the world

Source