If indeed there be a god in heaven. - Homer

Man is the vainest of all
creatures that have their being upon earth. As long as heaven
vouchsafes him health and strength, he thinks that he shall come to
no harm hereafter, and even when the blessed gods bring sorrow upon
him, he bears it as he needs must, and makes the best of it; for
God Almighty gives men their daily minds day by day. I know all
about it, for I was a rich man once, and did much wrong in the
stubbornness of my pride, and in the confidence that my father and
my brothers would support me; therefore let a man fear God in all
things always, and take the good that heaven may see fit to send
him without vainglory.

Ὣς ἄρα φωνήσαντε καθ' ἵππων ἀΐξαντε
χεῖράς τ' ἀλλήλων λαβέτην καὶ πιστώσαντο·
ἔνθ' αὖτε Γλαύκῳ Κρονίδης φρένας ἐξέλετο Ζεύς,
ὃς πρὸς Τυδεΐδην Διομήδεα τεύχε' ἄμειβε
χρύσεα χαλκείων, ἑκατόμβοι' ἐννεαβοίων.

Think not to match yourself against the gods, for men that walk the earth cannot hold their own with the immortals.