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प्रयत्नाद्यतमानस्तु योगी संशुद्धकिल्बिषः ।
अनेकजन्मसंसिद्धस्ततो याति परां गतिम् ॥६- ४५॥
prayatnaadyatamaanastu yogii saMshuddhakilbiShaH ।
anekajanmasaMsiddhastato yaati paraaM gatim ॥६- ४५॥
Source: Automatic ITRANS Transliteration
Continuing the effort with great effort, the yogi is purified from ignorance.
Achieving success in many births, thence achieves the supreme goal.
Source: Milind S. Pandit
The yogi who diligently strives, perfecting (gradually) through many incarnations, becomes completely free from all sins (or imperfections) and reaches the supreme goal (of Self-realization).
But when the yogi engages himself with sincere endeavor in making further progress, being washed of all contaminations, then ultimately, after many, many births of practice, he attains the supreme goal.
Source: Bhagavad Gita As It Is