Srimad Bhagavatam Canto 03, Chapter 14, Text 46

SB 3.14.46

yogair hemeva durvarnam
 bhavayisyanti sadhavah
nirvairadibhir atmanam
 yac-chilam anuvartitum
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
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.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
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. Prahlada Maharaja 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.
Srimad Bhagavatam Canto 03, Chapter 14, Text 44-45
Srimad Bhagavatam Canto 03, Chapter 14, Text 47