Bhagavad Gita: Chapter 6, Verse 43

तत्र तं बुद्धिसंयोगं लभते पौर्वदेहिकम् |
यतते च ततो भूय: संसिद्धौ कुरुनन्दन || 43||

tatra taṁ buddhi-sanyogaṁ labhate paurva-dehikam
yatate cha tato bhūyaḥ sansiddhau kuru-nandana

tatrathere; tamthat; buddhi-sanyogamreawaken their wisdom; labhateobtains; paurva-dehikamfrom the previous lives; yatatestrives; chaand; tataḥthereafter; bhūyaḥagain; sansiddhaufor aperfection; kuru-nandanaArjun, descendant of the Kurus

Translation

BG 6.43: On taking such a birth, O descendant of Kurus, they reawaken the wisdom of their previous lives, and strive even harder toward perfection in Yog.

Commentary

God, who is seated within the heart of every living being, is perfectly just. Whatever spiritual assets we had accumulated in the past life—detachment, wisdom, devotion, faith, tolerance, determination, etc.—are known to him. So, at the appropriate time, he gives us the fruits of our past efforts and enhances our spirituality from within, in accordance with our previous attainments. This explains why some people harboring materialistic views suddenly become deeply spiritual. When their spiritual sanskārs awaken, they get the benefit of their sādhanā of previous lives.

A traveler may break journey to rest the night in a hotel on the wayside. But when he wakes up, he does not need to again tread the distance already covered. He simply moves ahead to cover the remaining distance. Likewise, by God’s grace, the yogi of past lives receives the previous spiritual assets accumulated, to be able to continue the journey where he had left off, like someone who has woken up from sleep. That is why such a yogi never gets lost.