Vidura was successful in approaching such a spiritual master like Maitreya, and he got the ultimate goal of life: bhakti unto Govinda. Thus there was nothing to be known further about spiritual progress
SB Canto 1
After asking various questions and becoming established in the transcendental loving service of Lord Kṛṣṇa, Vidura retired from putting questions to Maitreya Muni.
Vidura retired from putting questions before Maitreya Muni when he was convinced by Maitreya Ṛṣi that the summum bonum of life is to be finally situated in the transcendental loving service of Lord Śrī Kṛṣṇa, who is Govinda, or one who satisfies His devotees in all respects. The conditioned soul, the living being in material existence, seeks happiness by employing his senses in the modes of materialism, but that cannot give him satisfaction. He then searches after the Supreme Truth by the empiric philosophic speculative method and intellectual feats. But if he does not find the ultimate goal, he again goes down to material activities and engages himself in various philanthropic and altruistic works, which all fail to give him satisfaction. So neither fruitive activities nor dry philosophical speculation can give one satisfaction because by nature a living being is the eternal servitor of the Supreme Lord Śrī Kṛṣṇa, and all the Vedic literatures give him direction towards that ultimate end. The Bhagavad-gītā (15.15) confirms this statement.
Like Vidura, an inquisitive conditioned soul must approach a bona fide spiritual master like Maitreya and by intelligent inquiries must try to know everything about karma (fruitive activities), jñāna (philosophical research for the Supreme Truth) and yoga (the linking process of spiritual realization). One who is not seriously inclined to put questions before a spiritual master need not accommodate a show-bottle spiritual master, nor should a person who may be a spiritual master for others pose to be so if he is unable to engage his disciple ultimately in the transcendental loving service of Lord Śrī Kṛṣṇa. Vidura was successful in approaching such a spiritual master like Maitreya, and he got the ultimate goal of life: bhakti unto Govinda. Thus there was nothing to be known further about spiritual progress.