In the Sixth Chapter He has explained the SANKHYA-yoga system and the concluding portion of the sankhya-yoga system is:
yoginam api sarvesam
mad-gatenantar-atmana
sraddhavan bhajate yo mam
sa me yuktatamo matah"
(Bhagavad-gita 6.47 - Ahmedabad, December 12, 1972)
"Thus end the Bhaktivedanta Purports to the Sixth Chapter of the Srimad-Bhagavad-gita in the matter of SANKHYA-yoga Brahma-vidya."
(Bg AII 6.47)
"Thus ends the Bhaktivedanta Purports for the Sixth Chapter of Srimad Bhagavad Gita, in the matter of SAMKHYA yoga Brahma vidya"
(Prabhupada's draft)
"How can we sit down silently and do nothing? It is not possible. Therefore, after Sri Krsna outlined the SANKHYA-yoga system in the Sixth Chapter of Bhagavad-gita,..."
(Path of Perfection 1: Yoga as Action)
"...Thus end the Bhaktivedanta purports to the Fifth Chapter of the Srimad Bhagavad-gita on the subject of karma-yoga or acting in Krsna consciousness."
Prabhupada: All right. Then we shall... SANKHYA-yoga shall I begin today or next day? This is a new chapter, we shall begin next day. (end)"
(Bhagavad-gita 5.26-29 - Los Angeles, February 12, 1969)
"That means one who is keeping always in Krsna consciousness, "abides in Me with great faith, worshiping Me in transcendental loving service is most intimately united with Me in yoga, and is the highest of all." This is the prime instruction of this chapter, SANKHYA-yoga, that if you want to become perfect yogi of the highest platform, then keep yourself in Krsna consciousness and you become the first-class yogi."
(Bhagavad-gita 6.46-47 -- Los Angeles, February 21, 1969)
That is also stated in the SANKHYA-Yoga chapter of Bhagavad-gita:
yoginam api sarvesam
mad-gatenantar-atmana
sraddhavan bhajate yo mam
sa me yuktatamo matah
[Bg. 6.47]
(Bhagavad-gita 7.1 - Calcutta, January 27, 1973)
Jayadvaita Swami's changed Bhagavad-gita So-called As It Is, which says DHYANA-yoga for the sixth chapter IN SPITE of Srila Prabhupada calling it SANKHYA-yoga in many, many places.
Question arises: This seems such a NEEDLESS change. How dare one correct Srila Prabhupada on this one?