vadho brahma-vadhad guruh
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
My dear son, killing a king who is an emperor is more severely sinful than killing a brahmana. But now, if you become Krsna conscious and worship the holy places, you can atone for this great sin.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
One who fully surrenders to the Supreme Personality of Godhead is freed from all sins (aham tvam sarva-papebhyo moksayisyami). From the very day or moment he fully surrenders to Sri Krsna, even the most sinful person is freed. Nonetheless, as an example, Jamadagni advised his son Parasurama to worship the holy places. Because an ordinary person cannot immediately surrender to the Supreme Personality of Godhead, he is advised to go from one holy place to another to find saintly persons and thus gradually be released from sinful reactions.
Thus end the Bhaktivedanta purports of the Ninth Canto, Fifteenth Chapter, of the Srimad-Bhagavatam, entitled “Parasurama, the Lord’s Warrior Incarnation.”