SB 3.19.32
maya yathanuktam avadi te hareh
krtavatarasya sumitra cestitam
yatha hiranyaksa udara-vikramo
maha-mrdhe kridanavan nirakrtah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Maitreya continued: My dear Vidura, I have explained to you the Personality of Godhead’s coming down as the first boar incarnation and killing in a great fight a demon of unprecedented prowess as if he were just a plaything. This has been narrated by me as I heard it from my predecessor spiritual master.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Here the sage Maitreya admits that he explained the incident of the killing of Hiranyaksa by the Supreme Personality of Godhead as a straight narration; he did not manufacture anything or add interpretation, but explained whatever he had heard from his spiritual master. Thus he accepted as bona fide the system of parampara, or receiving the transcendental message in disciplic succession. Unless received by this bona fide process of hearing from a spiritual master, the statement of an acarya or preceptor cannot be valid.
It is also stated here that although the demon Hiranyaksa was unlimited in prowess, he was just like a doll for the Lord. A child breaks so many dolls without real endeavor. Similarly, although a demon may be very powerful and extraordinary in the eyes of an ordinary man in the material world, to the Lord, killing such a demon is no difficulty. He can kill millions of demons as simply as a child plays with dolls and breaks them.