Swami said that Lord Krishna actually spoke only five verses and the remaining 695 verses were written by Vyasa. Has Swami mentioned elsewhere what these five particular shlokas are?
Swami gave a series of discourses on the Bhagavad Gita, explaining many Shlokas/verses (more than 5) from the sacred text. It is well documented both in the Divine Discourses, and in His writings in the GitaVahini. Swami expounded on the teachings of Lord Krishna as found in many chapters of the Bhagavad Gita. The reference quote given in the Sathya Sai with Students blog is not found in His discourses or writings. But, Swami commented that for the redemption of mankind, diving deep into one Shloka and practicing it is more beneficial than memorising all 700 Shlokas. He compared this to a matchbox with 700 match sticks – only one good match stick is enough to light a lamp. Similarly, to light the lamp of love and realise the Atman, you need only practice the essence of one Shloka – that will suffice.