Lucretius

One thing I fear now is that you may think
There's something impious in philosophy
And that you are entering on a path of sin.
Not so. More often has religion itself
Given birth to deeds both impious and criminal:
As once at Aulis the leaders of the Greeks,
Lords of the host, patterns of chivalry,
The altar of the virgin goddess stained
Most foully with the blood of Iphianassa.
The braiding band around her maiden locks
Dropped down in equal length on either cheek;
She saw her father by the altar stand
In sorrow, the priests beside him hiding knives,
And all the people weeping when they saw her;
Then dumb with fear she sank down on her knees.
Nor could it help, poor girl, at such a time
That she first gave the king the name of father.
For men's hands lifted her and led her on
Pale, trembling, to the altar, not indeed
That in fulfillment of the ancient rite
The brilliant wedding hymns should be her escort,
But that a stainless victim foully stained,
At the very age of wedlock, sorrowing,
She should be slaughtered by a father's blade,
So that a fleet might gain a favoring wind.
So great the power religion had for evil.