Of all the things Locke has to say about natural rights, the principle of extreme necessity strikes people today as the strangest element of his thought. It is the single element of his natural rights theory that has been lost; most people today have never heard of it and react with disbelief when it is explained. That principle, which was nevertheless a commonplace of medieval theology and church law, states, simply enough, that a person in extreme necessity—that is, facing the prospect of certain, not necessarily instant, death—may rightfully take the property of other people to sustain his life. This principle is the most radical formulation of the medieval belief that God had bestowed the earth upon all mankind for its sustenance, and it came into play only in extreme circumstances when an individual’s subsistence needs had failed to be satisfied by his own resources, by his family, and by his community.
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