One who kidnaps a Jew, sells him, and is later caught is liable to the death penalty, for it is written in the Torah: “And if you find a man who has kidnapped from among his brothers, for the people of Israel, making use of him, or selling him, then that thief shall die” (Deuteronomy 24:7).
The sages explained that two conditions must be met to make a person liable to the death penalty: 1. The kidnapper makes use of the kidnapped person 2. The kidnapper sells the kidnapped person.
One of the Talmudic sages asked: What is the rule if one kidnaps a sleeping person and before the person awoke sold him, after using him as a surface to lean upon? He also asked: what is the rule for a person who kidnapped a pregnant woman, planning to sell only the fetus, and the use made of the fetus is that the pregnant woman was stood in a doorway to block an annoying draft. (The fetus was used to enlarge the bulk of the woman’s belly so she blocked more of the annoying draft.)
What are the issues under debate? On one hand, since these sorts of uses are rare, they may not be considered usage and so do not make someone liable to the death penalty. On the other hand, in the final analysis use was made of the kidnapped people, and so the kidnapper should be liable to the death penalty. (The Talmud did not reach a decision on this issue.)
(Babylonian Talmud Tractate Sanhedrin 85b)