Thomas Bulfinch,
Bulfinch's Mythology
“ Pirithous had made an irruption into the plain of Marathon, and carried off the herds of the king of Athens. Theseus went to repel the plunderers. The moment Pirithous beheld him, he was seized with admiration; he stretched out his hand as a token of peace, and cried, "Be judge thyself—what satisfaction dost thou require?" "Thy friendship," replied the Athenian, and they swore inviolable fidelity. Their deeds corresponded to their professions, and they ever continued true brothers in arms. ”
