Do as you please, Zeus…
but none of the deathless gods will ever praise you.
And I tell you this – take it to heart, I urge you –
if you send Sarpedon home, living still, beware!
Then surely some other god will want to sweep
his own son clear of the heavy fighting too.

– Homer

The Iliad, Book 16, lines 526-531. Zeus sees that his son Sarpedon is about to be killed in the war between Trojans and Achaeans. He considers saving his son, but here Hera argues that if he interferes it will open the door to other gods to meddle too much in human affairs. So Zeus puts his duty to the other gods before his love for his son.