Christ's allegories were his attempts to explain the supernatural where God exists to the natural where we exist. The natural realm was created and is sustained by God but is only an echo or shadow of the highest supernatural realm, heaven.
For example how does one explain the Kingdom of God which is unlike any earthly kingdom? Christ even says "to what can I compare the kingdom of God?".
When talking about "the law" of the Old Testament, it's important for everyone to understand that there is God's law, the 10 commandments, and the Mosaic law, which Moses set forth in Leviticus, Numbers, etc. and which everyone likes to bastardize and quote.
Jesus mentions that the mosaic law included a 'letter of the law' interpretation of the 10 commandments, which is incorrect. Jesus said you judge by the letter of the law rather than with reason, judging righteously, meaning there are situations and circumstances that need to be judged accordingly. Additionally, this is why Jesus taught that if you lust after a woman you commit adultery even if you don't actually commit the physical act.
Jesus did not abolish the Mosaic law, but rather he fulfilled it, which was previously impossible for everyone else. By fulfilling the law perfectly he freed everyone else from it. This is what Paul explains in Romans. This is why we CAN each previously "unclean" animals, and why we don't need to be circumcised, etc. God's law; however, remains in effect. DO NOT believe any 'pastors' when they say we are no longer under the 10 commandments.
Satan is a living entity just as demons and angels are living entities, but they do not have bodies.
They are purely spirits so they do not "float" anywhere. They operate above the natural realm in the preternatural realm; therefore, they operate differently than we do in physical space. They have the ability to bi-locate for example.