yogair hemeva durvarṇaṁ
yogaiḥ—by the rectifying processes; hema—gold; iva—like; durvarṇam—inferior quality; bhāvayiṣyanti—will purify; sādhavaḥ—saintly persons; nirvaira-ādibhiḥ—by practice of freedom from animosity, etc.; ātmānam—the self; yat—whose; śīlam—character; anuvartitum—to follow in the footsteps.
In order to follow in his footsteps, saintly persons will try to emulate his character by practicing freedom from animosity, just as the purifying processes rectify gold of inferior quality.
Yoga practice, the process of purifying one’s existential identity, is based mainly on self-control. Without self-control one cannot practice freedom from animosity. In the conditional state, every living being is envious of another living being, but in the liberated state there is an absence of animosity. Prahlāda Mahārāja was tortured by his father in so many ways, yet after the death of his father he prayed for his father’s liberation by the Supreme Personality of Godhead. He did not ask any benediction that he might have asked, but he prayed that his atheistic father might be liberated. He never cursed any of the persons who engaged in torturing him at the instigation of his father.
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