Swami Sivananda in his commentary has prescribed the one Sloka 78 of Chapter 18 of Bhagawad Gita as एकश्लोकी गीता. He has also compiled a सप्तश्लोकी गीता with seven Slokas from Gita. One can read, understand and ponder over.
I shall like to provide the first one here:
यत्र योगेश्वरः कृष्णो यत्र पार्थो धनुर्धरः ।
तत्र श्रीर्विजयो भूतिर्ध्रुवा नीतिर्मतिर्मम ॥
Wherever is Krishna, the Lord of Yoga, wherever is Partha, the archer, there are prosperity (श्री), victory or success(विजय),happiness and sound policy(भूति);this is my conviction.
It is Sanjaya, the charioteer of Dhritarashtra, the blind king of Kuru with special power of seeing the Mahabharata battle in every audio and visual detail bestowed by Vyasa, who is giving his last opinion after the completion of the conversation between Arjuna and Krishna expecting from the old king to make stop the devastating forthcoming battle of Mahabharata at last. But it didn’t happen.
However, Vyasa wishes to give expression of a deeper significance through this verse- expounding an unquestionable truth.
Krishna in Gita everywhere represented the Self, the Atman.He can be invoked within heart of each one of us, if we try for the Atman through the prescribed exercises for Self-realisation. We all are like Arjun-Partha Dhanurdharah who represents “the confused, mortal human being , with all innumerable emotional weaknesses and fears”. Just after seeing the huge army of his own close relatives, Arjuna hesitated to use his talent to destroy and defeat them, though the whole lot of them are on wrong side of dharma, and laid down his arms and decided for not taking the right route to fight the wrong ones, reclined to impotent idleness. But then Krishna by answering all his queries and convincingly explaining the need to fight made him take up arms.
We all can win the battle that we face in life every time by invoking the Ataman, the Krishna in us.Once reinforced with spiritual understanding ,we can exert and put the required endeavours, to tame life and master prosperity.No power on the earth can stop us from success.