Tractate Shevuot - Chapter 5 - Mishnah 5 שבועות פרק ה׳ משנה ה׳

“You stole my ox,” and he says, “I have not stolen it” “I adjure You,” and he responds, “Amen!” he is liable. “I have stolen it, but I have not killed it or sold it”, “I adjure you,” and he responds, “Amen!” he is exempt. “Your ox killed my ox,” and he says, “It did not kill [your ox]”, “I adjure you,” and he responds, “Amen!” he is liable. “Your ox killed my slave,” and he says, “It did not kill [your slave]”, “I adjure you,” and he responds, “Amen!” he is exempt. He said to him, “You injured me, or bruised me,” and the other says, “I have not injured you or bruised you,” “I adjure you,” and he responds, “Amen!” he is liable. His slave said to him, “You knocked out my tooth, or blinded my eye,” and he said, “I did not knock out [your tooth], or blind [your eye],’ “I adjure you,” and he responds, “Amen!” he is exempt. This is the principle: whenever he pays on his own admission, he is liable; and when he does not pay on his own admission, he is exempt.