9.2 Raja-etc.  Shines :  that which illumines in the midst of all sciences.  Here [in the Gita]  itself it is said 'The science of the Self  [is the chief] among the sciences'.  Here in this science kings like  Janaka etc., have a right and pervilege  (adhikara)  [to learn].  It is their secret, as it is much protected  (by them)  by heroism easy for the  Ksatriyas.  As they do not waver [in their mind]  because of their heroic nature that is common in the members of the warring class, it is very easy to do i.e.,  to observe.  Imperishable :  Unlike other actions this action of worshipping  Brahman does not perish through the enjoyment of  [its result].