In His House
A mathematical axiom tells us that if a = b, then b = a. The Gemara says that one should dwell in the sukkah as one usually dwells in his house. The reverse must also be true: one should dwell in his house with the same kedusha and respectful attitude as one dwells in the sukkah. The sukkah is called "tzila dimehemenusa", a shelter of emuna. At home one lives under the shelter of emuna, and should conduct himself accordingly.