SB 2.4.1
suta uvaca
vaiyasaker iti vacas
tattva-niscayam atmanah
upadharya matim krsne
auttareyah satim vyadhat
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Suta Gosvami said: Maharaja Pariksit, the son of Uttara, after hearing the speeches of Sukadeva Gosvami, which were all about the truth of the self, applied his concentration faithfully upon Lord Krsna.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The word satim is very significant. This means “existing” and “chaste.” And both imports are perfectly applicable in the case of Maharaja Pariksit. The whole Vedic adventure is to draw one’s attention entirely unto the lotus feet of Lord Krsna without any diversion, as instructed in the Bhagavad-gita (15.15). Fortunately Maharaja Pariksit had already been attracted to the Lord from the very beginning of his body, in the womb of his mother. In the womb of his mother he was struck by the brahmastra atomic bomb released by Asvatthama, but by the grace of the Lord he was saved from being burnt by the fiery weapon, and since then the King continuously concentrated his mind upon Lord Krsna, which made him perfectly chaste in devotional service. So by natural sequence he was a chaste devotee of the Lord, and when he further heard from Srila Sukadeva Gosvami that one should worship the Lord only and no one else, even though full of all desires or desireless, his natural affection for Krsna was strengthened. We have already discussed these topics.
To become a pure devotee of Lord Krsna, two things are very much essential, namely having a chance to be born in the family of a devotee and having the blessings of a bona fide spiritual master. By the grace of Lord Krsna, Pariksit Maharaja had both opportunities. He was born in a family of such devotees as the Pandavas, and just to continue the dynasty of the Pandavas and show them special favor, the Lord specifically saved Maharaja Pariksit, who later on, by the arrangement of the Lord, was cursed by the boy of a brahmana and was able to get the association of such a spiritual master as Sukadeva Gosvami. In the Caitanya-caritamrta it is said that a fortunate person, by the mercy of the spiritual master and Lord Krsna, achieves the path of devotional service. This was perfectly applicable in the case of Maharaja Pariksit. By way of being born in a family of devotees, he automatically came in touch with Krsna, and after being so contacted he constantly remembered Him. Consequently Lord Krsna gave the King a further chance for development in devotional service by introducing him to Sukadeva Gosvami, a stalwart devotee of the Lord with perfect knowledge in self-realization. And by hearing from a bona fide spiritual master, he was perfectly able to concentrate his chaste mind further upon Lord Krsna, as a matter of course.