Bhagavad Gita · Sankhya YogaChapter 2, Shloka 61 (2.61)

"Mat-paraḥ" — two readings.

• Shankaracharya: ahaṃ vāsudevaḥ sarva-pratyag-ātmā paro yasya sa mat-paraḥ; na anyo 'haṃ tasmāt iti āsīta — "one for whom I, Vasudeva, the inner self of all, am supreme" — and he should remain in the awareness "I am not different from him". That is, the Advaita reading: the sense of non-difference from the inner self.
• Ramanujacharya: cetasaḥ śubhāśraya-bhūte mayi manaḥ avasthāpya — fixing the mind on me, the auspicious support (holy refuge) for the mind. The mind fixed on the Lord — as all its kalmasha (impurities) are burnt away — becomes pure and free of attachment to sense objects, and then brings the senses under control.

Ramanuja — the resolution of the circle of 2.60. In 2.60 Ramanuja said: victory over the senses depends on seeing the self, and seeing the self on victory over the senses. Here is the answer: fixing the mind on the Lord breaks this circle. He gives a shloka from the Vishnu Purana (6.7.74): just as a fire with tall flames, fanned by the wind, burns up dry grass, so Vishnu, dwelling in the mind, burns up all the sins of yogis.

At the end of 2.61 Ramanuja also says: evaṃ mayi aniveśya manaḥ sva-yatna-gauraveṇa indriya-jaye pravṛtto vinaṣṭo bhavati — one who, without fixing the mind on me, sets about conquering the senses relying only on his own effort, is ruined. This lays the ground for the next two shlokas (2.62–2.63).