From the Martyrdom of St. Polycarp (AD 69-155) Chapter 9.

Now, as Polycarp was entering into the stadium, there came to him a voice
from heaven, saying, "Be strong, and show thyself a man, O Polycarp !" No one
saw who it was that spoke to him; but those of our brethren who were present
heard the voice. And as he was brought forward, the tumult became great when
they heard that Polycarp was taken. And when he came near, the proconsul asked
him whether he was Polycarp. On his confessing that he was, [the proconsul]
sought to persuade him to deny [Christ], saying, "Have respect to thy old
age," and other similar things, according to their custom, [such as]," Swear
by the fortune of Caesar; repent, and say, Away with the Atheists." But
Polycarp, gazing with a stern countenance on all the multitude of the wicked
heathen then in the stadium, and waving his hand towards them, while with
groans he looked up to heaven, said, "Away with the Atheists." Then, the
proconsul urging him, and saying, "Swear, and I will set thee at liberty,
reproach Christ;" Polycarp declared, "Eighty and six years have I served Him,
and He never did me any injury: how then can I blaspheme my King and my
Saviour?"

Read the whole thing at NewAdvent