Patanjali's is the ultimate inclusive system. It is so rational an approach to the spiritual project...

For 1.36 - could light mean the Sun as well an internal light we can meditate on, or would that be more in the realm of   Īśvarapraṇidhāna?    Because the Sun is the totality of the spectrum..And for 1.39 - isn't it typical that you are given an open ended option which is as tricky to use as any of the preceding options?  Choice is as hard as being bound to one technique.  I used to think 1.39 as the ultimate in inclusivity but it requires as much presence, diligence and wholehearted effort as anything else more specific...so work to do...to realise 1.39.  Advanced !

In the Quaker practice, inner guidance (maybe the equivalent of God) is refered to as "the light". A higher voice within so to speak. Maybe there is a link there (1.36)...