“There are 39 categories of prohibited work…learned from the labors that were needed in the Mishkan… If by working six days, I proclaim my mastery over the physical world, then by resting on the seventh day, I am saying ‘but there is a greater Master over the physical world and that is G-d.’

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This works well for 38 of the 39 categories of work, [but] the prohibition of carrying…does not show mastery over anything. …Rav Hirsch says that…taking from the private domain into the community and taking from the community into the private domain. This is the social interaction of human beings. The sum total of all human social interactions can be called ‘history’.

When I refrain from carrying on Shabbos, I am making the statement, that not only is G-d Master over the physical world, but G-d is Master over social interaction. G-d is Master over history.

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This, says R. Samson Raphael Hirsch, is what we say in the Shabbos Kiddush – Shabbos is ‘in commemoration of the Exodus from Egypt’ and it is ‘in commemoration of the Act of Creation’. The Act of Creation is the fact that we acknowledge (by abstaining from 38 types of labor) that G-d created the physical world. The Exodus is the fact that we acknowledge (by refraining from carrying) the Hand of G-d in the history of human beings.”