Purport

In earlier Shloka Bhagvan Shri Krishna explained living being is strongly bounded with the material nature that is Maya. All senses and even mind is a material structure that cannot sense anything beyond matter and effects of three Gunas. Hence humans cannot witness God in a normal situation because God exists beyond the boundary of material nature and modes of nature(satva, rajasa, tamasa).

But in this Shloka Bhagvan Shri Krishna further describes that though witnessing Him(God Shri Krishna) is difficult but not impossible. Those humans who are able to surpass the experience of sense organ and mind are able to see God. That state can be achieved by following any path of Yoga. But again following any path of Yoga is not easy. Bhagvan Shri Krishna gives the even easier option, and that is the devotion. Bhagvan Says that through devotion it is easier to cross the limits of Maya. Once a human able to cross the limits of Maya is able to see God.

This Shloka hence once again confirms the glory of devotion (Bhakti Yoga) over other methods