Mental satisfaction means feeling happy and peaceful. Attaining happiness has nothing to do with religion. To be sure, in the scriptures we can find lots of specifically Buddhist doctrines, but the Buddha also gave many teachings which are quite universal in nature. Most people believe that happiness comes from favorable material conditions, but this is a myth, for we can’t always get everything we want. But when the mind is under control, we can be very happy, even if we are lacking on the material level.
~Khangser Rinpoche~