Karma-yoga and Sannyasa are same, because both lead to spiritual realization and have same conclusion
Most of the points are covered in the Summarized Theme 5A table below)
aHow Sankhya and Karma-yoga / Devotional Service are the same — Because the common aim is “Vishnu” (5.4 purport)
bWho sees things as they are — One who sees Sankhya (analytical study) and devotional service on the same level in terms of aim (5.5)
cAim of analytical study of material world — find the soul of existence
Soul of material world—Vishnu / Devotional service entails service to the Supersoul
Analogy: One is to find the root of tree (Sankhya), other is to water the root (Devotional Service).
dReal purpose of philosophical research is to find the ‘Ultimate Goal of Life’, which is ‘self- realization’. This proves there is no difference between the conclusion of the two processes (5.5)
LINK BETWEEN TEXTS 5.5 & 5.6 — It is important to understand that Krishna is not speaking about a variety of paths leading to a variety of inferior or superior destinations. Rather, He is describing two aspects of a path—one easy and one difficult—with the same goal. (These verses are applicable to anyone trying to attain Brahman, Paramatma or Bhagavan realization, but Srila Prabhupada translated yoga as “devotional service” to highlight Krishna’s actual desire and purpose.) If we renounce activities before our hearts are clean, we will be forced by our unclean hearts to engage in improper activities. The senses will demand engagement, but the jnana-yoga process forbids sense activity. Unless the senses are engaged in good work, it will be difficult to stop improper work. Krishna therefore recommends keeping the senses always engaged, while simultaneously purifying the heart by working with detachment. This is the more practical and, therefore, superior path. The comparison between the two paths continues in the following verse.