Little is known of the lives of these two 1st century martyrs, whose graves are among the eariest honored by the Church. It is thought that they were soldiers, possibly members of the praetorian guard. Pope Damascus wrote a poetic epitaph for them in the fourth century, and though the slab on which is was inscibed is nearly destoyed by time, copies of its text made by ancient travelers have retained the words:
The martyrs Nereus and Achilleus had enrolled themselves in the army and exercised the cruel office of carrying out the orders of the tyrant, being ever ready, through the constraint of fear, to obey his will. O miracle of faith! Suddenly they cease from their fury, they become converted, they fly from the camp of their wicked leader; they throw away their shields, their armor and their blood-stained javelins. Confessing the faith of Christ, they rejoice to bear testimony to its triumph. Learn now from the words of Damasus what great things the glory of Christ can accomplish.”
It is believed that Nereus and Achilleus were beheaded. Their bodies were buried in the Catacomb of Domitilla on the Via Ardeatina and in the latter part of the 4th century a Church was built over their resting place.
(Adapted from Catholic Encyclopedia 1913, Robert Appleton Company, public domain.)