CC Ādi 1.63
tīrtha-bhūtāḥ svayaṁ vibho
This verse was spoken by Mahārāja Yudhiṣṭhira to Vidura in Śrīmad-Bhāgavatam (1.13.10). Mahārāja Yudhiṣṭhira was receiving his saintly uncle Vidura, who had been visiting sacred places of pilgrimage. Mahārāja Yudhiṣṭhira told Vidura that pure devotees like him are personified holy places because the Supreme Personality of Godhead is always with them in their hearts. By their association, sinful persons are freed from sinful reactions, and therefore wherever a pure devotee goes is a sacred place of pilgrimage. The importance of holy places is due to the presence there of such pure devotees.